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Tim Berners-Lee Sir Timothy John "Tim" Berners-Lee, OM, KBE, FRS, FREng, FRSA (born 8 June 1955),[1] also known as "TimBL", is a Britishcomputer scientist, MIT professor and the inventor of the World Wide Web. He made a proposal for an information management system in March 1989,[2SONY Vaio PCG-K215M Laptop Keyboard ] and on 25 December 1990, with the help of Robert Cailliau and a young student at CERN, he implemented the first successful communication between a Hypertext Transfer Protocol (HTTP) client and server via the Internet.[3]APPLE Macbook 13 Inch Laptop Keyboard Berners-Lee is the director of the World Wide Web Consortium (W3C), which oversees the Web's continued development. He is also the founder of the World Wide Web Foundation, and is a senior researcher and holder of the Founders Chair at the MIT Computer Science and Artificial Intelligence Laboratory (CSAIL).[4] He is a director of the Web Science Research Initiative (WSRI),[5] and a member of the advisory board of the MIT Center for Collective Intelligence.[6][7]HP Pavilion G7-1150US Laptop Keyboard In 2004, Berners-Lee was knighted by Queen Elizabeth II for his pioneering work.[8] In April 2009, he was elected a foreign associate of the United States National Academy of Sciences.[9][10] He was honoured as the 'Inventor of the World Wide Web' in a section of the 2012 Summer Olympics opening ceremony[11]ACER Aspire 5810T Laptop Keyboard in which he appeared in person, working at a NeXT Computer at the London Olympic Stadium. He tweeted "This is for everyone",[12] which was instantly spelled out in LCD lights attached to the chairs of the 80,000 people in the audience.[13]TOSHIBA Mini NB 255-SP1002M Laptop Keyboard

Early life

Berners-Lee was born in southwest London, England, on 8 June 1955, one of four children born to Conway Berners-Lee and Mary Lee Woods. His parents worked on the first commercially-built computer, the Ferranti Mark 1. He attended Sheen Mount Primary School, and then went on to attend London's Emanuel School from 1969 to 1973.[8] He studied at Queen's College,Oxford, from 1973 to 1976, where he received a first-class degree in physics.[1]DELL Inspiron N4050 Laptop Keyboard Berners-Lee worked as an independent contractor at CERN from June to December 1980. While there, he proposed a project based on the concept of hypertext, to facilitate sharing and updating information among researchers.[14] To demonstrate, he built a prototype system named ENQUIRE.[15]HP Pavilion dv6-2020sa Laptop Keyboard After leaving CERN in late 1980, he went to work at John Poole's Image Computer Systems, Ltd, in Bournemouth, England.[16] The project he worked on was a real-time remote procedure call which gave him experience in computer networking.[16] In 1984, he returned to CERN as a fellow.[15] DELL Vostro PP37L Laptop Keyboard In 1989, CERN was the largest Internet node in Europe, and Berners-Lee saw an opportunity to join hypertext with the Internet: "I just had to take the hypertext idea and connect it to the Transmission Control Protocol and domain name system ideas and—ta-da!—the World Wide Web[17] ... Creating the web was really an act of desperation, HP G61-110SA Laptop Keyboard because the situation without it was very difficult when I was working at CERN later. Most of the technology involved in the web, like the hypertext, like the Internet, multifont text objects, had all been designed already. I just had to put them together. It was a step of generalising, going to a higher level of abstraction, thinking about all the documentation systems out there as being possibly part of a larger imaginary documentation system.”[18]SONY NSK-S8101 Laptop Keyboard Berners-Lee wrote his initial proposal in March 1989, and in 1990, with the help of Robert Cailliau (with whom he shared the 1995 ACM Software System Award), produced a revision which was accepted by his manager,  HP G61 Laptop Keyboard Mike Sendall.[19] He used similar ideas to those underlying the ENQUIRE system to create the World Wide Web, for which he designed and built the first Web browser. This also functioned as an editor (WorldWideWeb, running on the NeXTSTEP operating system), and the first Web server, CERN HTTPd (short for Hypertext Transfer Protocol daemon). DELL Alienware M11x Laptop Keyboard The first website built was at CERN within the border of France[21], and was first put online on 6 August 1991: "Info.cern.ch was the address of the world's first-ever web site and web server, running on a NeXT computer at CERN. The first web page address washttp://info.cern.ch/hypertext/WWW/TheProject.html, which centred on information regarding the WWW project. TOSHIBA NB200-10J Laptop Keyboard Visitors could learn more about hypertext, technical details for creating their own webpage, and even an explanation on how to search the Web for information. There are no screenshots of this original page and, in any case, changes were made daily to the information available on the page as the WWW project developed. You may find a later copy (1992) on the World Wide Web Consortium website." -CERNHP 519265-001 Laptop Keyboard It provided an explanation of what the World Wide Web was, and how one could use a browser and set up a web server.[22][23][24][25] In 1994, Berners-Lee founded the W3C at MIT. It comprised various companies that were willing to create standards and recommendations to improve the quality of the Web. Berners-Lee made his idea available freely, with no patent and no royalties due. The World Wide Web Consortium decided that its standards should be based on royalty-free technology, so that they could easily be adopted by anyone.[26]HP Mini 110-3118cl Laptop Keyboard In 2001, Berners-Lee became a patron of the East Dorset Heritage Trust, having previously lived in Colehill in Wimborne, East Dorset, England.[27] In December 2004, he accepted a chair in Computer Science at the School of Electronics and Computer Science, University of Southampton, England, to work on theSemantic Web.[28][29]ASUS F82Q Laptop Keyboard In a Times article in October 2009, Berners-Lee admitted that the initial pair of slashes ("//") in a web address were actually "unnecessary". He told the newspaper that he could easily have designed URLs not to have the slashes. "There you go, it seemed like a good idea at the time," he said in his lighthearted apology.[30] HP Mini 110-3118cl Laptop Keyboard

Current work

In June 2009 then British Prime Minister Gordon Brown announced Berners-Lee would work with the UK Government to help make data more open and accessible on the Web, building on the work of the Power of Information Task Force.[31] Berners-Lee and ProfessorNigel Shadbolt are the two key figures behind data.gov.  IBM Lenovo Thinkpad X201 Laptop Keyboard uk, a UK Government project to open up almost all data acquired for official purposes for free re-use. Commenting on the opening up of Ordnance Survey data in April 2010 Berners-Lee said that: "ACER Aspire 5742 Laptop Keyboard The changes signal a wider cultural change in Government based on an assumption that information should be in the public domain unless there is a good reason not to—not the other way around." He went on to say "Greater openness, accountability and transparency in Government will give people greater choice and make it easier for individuals to get more directly involved in issues that matter to them."[32]TOSHIBA MP-09K53US6698 Laptop Keyboard In November 2009, Berners-Lee launched the World Wide Web Foundation in order to "Advance the Web to empower humanity by launching transformative programs that build local capacity to leverage the Web as a medium for positive change."[33] HP 576835-001 Laptop Keyboard Berners-Lee is one of the pioneer voices in favour of Net Neutrality,[34] and has expressed the view that ISPs should supply "connectivity with no strings attached," and should neither control nor monitor customers' browsing activities without their expressed consent.[35][36] He advocates the idea that net neutrality is a kind of human network right: "Threats to the Internet, such as companies or governments that interfere with or snoop on Internet traffic, compromise basic human network rights."[37]HP Envy 15 Laptop Keyboard Berners-Lee is a co-director of the Open Data Institute.[38]

Robert Cailliau

Cailliau was born in Tongeren, Belgium. In 1958 he moved with his parents to Antwerp. After secondary school he graduated from Ghent University in 1969 as civil engineer in electrical and mechanical engineering (Flemish: Burgerlijk Werktuigkundig en Elektrotechnisch ingenieur). He also has an MSc from the University of Michigan in Computer, Information and Control Engineering, 1971. HP 576835-001 Laptop Keyboard During his military service in the Belgian Army he maintained Fortran programs to simulate troop movements.[1] In December 1974 he started working at CERN as a Fellow in the Proton Synchrotron (PS) division, working on the control system of the accelerator. In April 1987 he left the PS division to become group leader of Office Computing Systems in the Data Handling division.[2] In 1989,  ACER Aspire 5742 Laptop Keyboard im Berners-Lee proposed a hypertext system for access to the many forms of documentation at and related to CERN.[3] Berners-Lee created the system, calling it World Wide Web, between September to December 1990. During this time, Cailliau and he co-authored a proposal for funding for the project.[4] Cailliau later became a key proponent of the project and developed with Nicola Pellow the first web browser for the Mac OS operating system called MacWWW.[4][5][6][7]ACER Aspire 5930 Laptop Keyboard In 1993, in collaboration with the Fraunhofer Gesellschaft Cailliau started the European Commission's first web-based project for information dissemination in Europe (WISE). As a result of his work with CERN's Legal Service, CERN released the web technology into the public domain on 30 April 1993. TOSHIBA Satellite L355 Laptop Keyboard In December 1993 Cailliau called for the first International WWW Conference which was held at CERN in May 1994.[4][8][9] The oversubscribed conference brought together 380 web pioneers and was a milestone in the development of the web. The conference led to the forming of the International World Wide Web Conferences Steering Committee which has organized an annual conference since then. Cailliau was a member of the Committee from 1994 until 2002. HP 576835-001 Laptop Keyboard In 1994 Cailliau started the "Web for Schools" project with the European Commission, introducing the web as a resource for education. After helping to transfer the web development from CERN to the World Wide Web Consortium, he devoted his time to public communication. He went on early retirement from CERN in January 2007. HP Envy 15 Laptop Keyboard Cailliau is now an active member of Newropeans, a transeuropean political movement for which he and Luca Cominassi have recently drafted a proposal concerning the European information society.[10]TOSHIBA P205-S7469 Laptop Keyboard He is a public speaker on the past and future of the World Wide Web and delivered the keynote opening speech at the annual Runtime Revolution developer conference in Edinburgh, Scotland on 1 September 2009. TOSHIBA 9J.N7482.901 Laptop Keyboard The European Organization for Nuclear Research (French: Organisation européenne pour la recherche nucléaire), known as CERN or Cern ( /ˈsɜrn/; French pronunciation: [sɛʁn]; see History) is an international organization whose purpose is to operate the world's largest particle physics laboratory, in the northwest suburbs of Geneva on the Franco–Swiss border (46°14′3″N 6°3′19″E). Established in 1954, the organization has 20 European member states. HP Mini 110-3135dx Laptop Keyboard The term CERN is also used to refer to the laboratory, which employs just under 2,400 full-time employees, 1,500 part-time employees, and hosts some 10,000 visiting scientists and engineers, representing 608 universities and research facilities and 113 nationalities. TOSHIBA Satellite L300 Laptop Keyboard CERN's main function is to provide the particle accelerators and other infrastructure needed for high-energy physics research. Numerous experiments have been constructed at CERN by international collaborations to make use of them. It is also the birthplace of the World Wide Web. SONY VAIO PCG-792L Laptop Keyboard The main site at Meyrin also has a large computer centre containing very powerful data-processing facilities primarily for experimental data analysis and, because of the need to make them available to researchers elsewhere, has historically been a major wide area networking hub.  HP 636376-001 Laptop Keyboard The convention establishing CERN was ratified on 29 September 1954 by 12 countries in Western Europe.[1] The acronym CERN originally stood in French for Conseil Européen pour la Recherche Nucléaire (European Council for Nuclear Research), which was a provisional council for setting up the laboratory, established by 12 European governments in 1952.  HP Mini 110-3118cl Laptop Keyboard The acronym was retained for the new laboratory after the provisional council was dissolved, even though the name changed to the current Organisation Européenne pour la Recherche Nucléaire (European Organization for Nuclear Research) in 1954.[2] IBM Lenovo ThinkPad X300 Laptop Keyboard According to Lew Kowarski, a former director of CERN, when the name was changed the acronym could have become the awkward OERN, and Heisenberg said that the acronym could "still be CERN even if the name is [not]".[citation needed] HP pavilion DV7-1000 Laptop Keyboard Soon after its establishment the work at the laboratory went beyond the study of the atomic nucleus into higher-energy physics, which is mainly concerned with the study of interactions between particles. Therefore the laboratory operated by CERN is commonly referred to as the European laboratory for particle physics (Laboratoire européen pour la physique des particules) which better describes the research being performed at CERN. HP 550 Laptop Keyboard The World Wide Web began as a CERN project called ENQUIRE, initiated by Tim Berners-Lee in 1989 and Robert Cailliau in 1990.[10] Berners-Lee and Cailliau were jointly honoured by theAssociation for Computing Machinery in 1995 for their contributions to the development of the World Wide Web. COMPAQ Presario CQ60-112EM Laptop Keyboard Based on the concept of hypertext, the project was aimed at facilitating sharing information among researchers. The first website went on-line in 1991. On 30 April 1993, CERN announced that the World Wide Web would be free to anyone. A copy[11] of the original first webpage, created by Berners-Lee, is still published on the World Wide Web Consortium's website as a historical document. HP Mini 110-3118cl Laptop Keyboard Prior to the Web's development, CERN had been a pioneer in the introduction of Internet technology, beginning in the early 1980s. A short history of this period can be found at CERN.ch.[12]SONY Vaio PCG-K215M Laptop Keyboard More recently, CERN has become a centre for the development of grid computing, hosting, among others, the Enabling Grids for E-sciencE (EGEE) and LHC Computing Grid projects. It also hosts the CERN Internet Exchange Point (CIXP), one of the two main internet exchange points in Switzerland.  HP Pavilion dv6-2112sa Laptop Keyboard

Faster-than-light neutrino anomaly

The LHC tunnel is located 100 metres underground, in the region between the Geneva International Airport and the nearby Jura mountains. It uses the 27 km circumference circular tunnel previously occupied by LEP which was closed down in November 2000. CERN's existing PS/SPS accelerator complexes will be used to pre-accelerate protons which will then be injected into the LHC. DELL Inspiron 6400 Laptop Keyboard Seven experiments (CMS, ATLAS, LHCb, MoEDAL[17] TOTEM, LHC-forward and ALICE) will run on the collider; each of them will study particle collisions from a different point of view, and with different technologies. TOSHIBA PK13CW10100 Laptop Keyboard Construction for these experiments required an extraordinary engineering effort. Just as an example, a special crane had to be rented from Belgium in order to lower pieces of the CMS detector into its underground cavern, since each piece weighed nearly 2,000 tons. The first of the approximately 5,000 magnets necessary for construction was lowered down a special shaft at 13:00 GMT on 7 March 2005. TOSHIBA Mini NB 505-SP0160 Laptop Keyboard This accelerator has begun to generate vast quantities of data, which CERN streams to laboratories around the world for distributed processing (making use of a specialised grid infrastructure, the LHC Computing Grid). In April 2005, a trial successfully streamed 600 MB/s to seven different sites across the world. If all the data generated by the LHC is to be analysed, then scientists must achieve 1,800 MB/s before 2008. SONY VAIO VGN-NR21J/S Laptop Keyboard The initial particle beams were injected into the LHC August 2008.[18] The first attempt to circulate a beam through the entire LHC was at 8:28 GMT on 10 September 2008,[19] but the system failed because of a faulty magnet connection, and it was stopped for repairs on 19 September 2008. HP 576835-001 Laptop Keyboard The LHC resumed operation on Friday 20 November 2009 by successfully circulating two beams, each with an energy of 3.5 trillion electron volts. The challenge that the engineers then faced was to try to line up the two beams so that they smashed into each other. This is like "firing two needles across the Atlantic and getting them to hit each other" according to the LHC's main engineer Steve Myers, director for accelerators and technology at the Swiss laboratory. HP Envy 15 Laptop Keyboard At 1200 BST on Tuesday 30 March 2010 the LHC successfully smashed two proton particle beams travelling with 3.5 TeV (trillion electron volts) of energy, resulting in a 7 TeV event. However, this is just the start of the road toward the expected discovery of the Higgs boson. This is mainly because the amount of data produced is so huge it could take up to 24 months to completely analyse it.  ACER Aspire 6930 Laptop Keyboard When the 7 TeV experimental period ended, the LHC revved up to 8 TeV (4 TeV acceleration in both directions) in March 2012, and will begin particle collisions at that rate in early April 2012. At the end of 2012 the LHC will be shut down for maintenance for up to two years, to strengthen the huge magnets inside the accelerator.  HP Mini 210-2006sa Laptop Keyboard It will then attempt to create 14 TeV events. In July 2012, CERN scientists claimed to have discovered a new sub-atomic particle that could be the much sought after Higgs boson believed to be essential for formation of the Universe.[20] SAMSUNG NP-N102-JA01DX Laptop Keyboard The smaller accelerators are on the main Meyrin site (also known as the West Area), which was originally built in Switzerland alongside the French border, but has been extended to span the border since 1965. The French side is under Swiss jurisdiction and there is no obvious border within the site, apart from a line of marker stones. There are six entrances to the Meyrin site:[citation needed]  Lenovo 3000 G530 4151 Laptop Keyboard GATEWAY MT6700 Laptop Keyboard The SPS and LEP/LHC tunnels are almost entirely outside the main site, and are mostly buried under French farmland and invisible from the surface. However they have surface sites at various points around them, either as the location of buildings associated with experiments or other facilities needed to operate the colliders such as cryogenic plants and access shafts. The experiments are located at the same underground level as the tunnels at these sites. TOSHIBA Satellite C650-182 Laptop Keyboard Three of these experimental sites are in France, with ATLAS in Switzerland, although some of the ancillary cryogenic and access sites are in Switzerland. The largest of the experimental sites is the Prévessin site, also known as the North Area, which is the target station for non-collider experiments on the SPS accelerator. Other sites are the ones which were used for the UA1, UA2 and the LEP experiments (the latter which will be used for LHC experiments). DELL Vostro 3700 Laptop Keyboard Outside of the LEP and LHC experiments, most are officially named and numbered after the site where they were located. For example, NA32 was an experiment looking at the production of charmed particles and located at the Prévessin (North Area) site while WA22 used the Big European Bubble Chamber (BEBC) at the Meyrin (West Area) site to examine neutrino interactions. The UA1 and UA2 experiments were considered to be in the Underground Area, i.e. situated underground at sites on the SPS accelerator.  HP Mini 110-1115SA Laptop KeyboardWide Area Network (WAN) is a telecommunication network that covers a broad area (i.e., any network that links across metropolitan, regional, or national boundaries). Business and government entities utilize WANs to relay data among employees, clients, buyers, and suppliers from various geographical locations. In essence this mode of telecommunication allows a business to effectively carry out its daily function regardless of location.[1] HP Pavilion G6-1B97CL Laptop Keyboard This is in contrast with personal area networks (PANs), local area networks (LANs), campus area networks (CANs), ormetropolitan area networks (MANs) which are usually limited to a room, building, campus or specific metropolitan area (e.g., a city) respectively. TOSHIBA Satellite 2410 PS241L-5Y34T Laptop Keyboard

Design options

The textbook definition of a WAN is a computer network spanning regions, countries, or even the world. However, in terms of the application of computer networking protocols and concepts, it may be best to view WANs as computer networking technologies used to transmit data over long distances, and between different LANs, SONY VAIO VGN-AR170P Laptop Keyboard MANs and other localised computer networking architectures. This distinction stems from the fact that common LAN technologies operating at Layer 1/2 (such as the forms of Ethernet or Wifi) are often geared towards physically localised networks, and thus cannot transmit data over tens, hundreds or even thousands of miles or kilometres. TOSHIBA Satellite 2410 PS241L-5Y34T Laptop Keyboard WANs necessarily do not just connect physically disparate LANs. A CAN, for example, may have a localised backbone of a WAN technology, which connects different LANs within a campus. This could be to facilitate higher bandwidth applications, or provide better functionality for users in the CAN. TOSHIBA Satellite L755-S5214 Laptop Keyboard WANs are used to connect LANs and other types of networks together, so that users and computers in one location can communicate with users and computers in other locations. Many WANs are built for one particular organization and are private. Others, built by Internet service providers, provide connections from an organization's LAN to the Internet. HP 576835-001 Laptop Keyboard WANs are often built using leased lines. At each end of the leased line, a router connects the LAN on one side with a second router within the LAN on the other. Leased lines can be very expensive. Instead of using leased lines, WANs can also be built using less costly circuit switching or packet switching methods.  FUJITSU Lifebook S6240 Laptop Keyboard Network protocols including TCP/IPdeliver transport and addressing functions. Protocols including Packet over SONET/SDH, MPLS, ATM and Frame relay are often used by service providers to deliver the links that are used in WANs. X.25 was an important early WAN protocol, and is often considered to be the "grandfather" of Frame Relay as many of the underlying protocols and functions of X.25 are still in use today (with upgrades) by Frame Relay. Compaq Presario CQ71-420ER Laptop Keyboard Academic research into wide area networks can be broken down into three areas: mathematical models, network emulation and network simulation. Performance improvements are sometimes delivered via wide area file services or WAN optimization. TOSHIBA Mini NB 505 Series Laptop Keyboard History The Information Technology Center, a partnership of Carnegie Mellon and IBM, began work on the Andrew Project in 1982.[1] In its initial phase, the project involved both software and hardware, including wiring the campus for data and developing workstations to be distributed to students and faculty at CMU and elsewhere. TOSHIBA Mini NB 505 Series Laptop Keyboard The proposed "3M computer" workstations included a million pixel display and a megabyte of memory, running at a million instructions per second. Unfortunately a fourth M, cost on the order of a megapenny (US$10,000), made the computers beyond the reach of students' budgets. HP Probook 4710S Keyboard The initial hardware deployment in 1985 established a number of university-owned "clusters" of public workstations in various academic buildings and dormitories. The campus was fully wired and ready for the eventual availability of inexpensive personal computers. SONY VAIO PCG-FR315M Keyboard Early development within the Information Technology Center, originally called VICE (Vast Integrated Computing Environment) and VIRTUE (Virtue Is Reached Through Unix and Emacs), focused on centralized tools, such as a file server, and workstation tools including a window manager, editor, email, and file system client code.[2]IBM Lenovo ThinkPad R51 1833 Keyboard HP 550 Keyboard Initially the system was prototyped on Sun Microsystems machines, and then to IBM 6150 RT series computers running a special IBM Academic Operating System.[3]People involved in the project included James H. Morris, Nathaniel Borenstein, James Gosling and David S. H. Rosenthal. TOSHIBA Satellite L775D-S7330 Keyboard The project was extended several times after 1985 in order to complete the software, and was renamed "Andrew" for Andrew Carnegie and Andrew Mellon, the founders of the institutions that eventually became Carnegie Mellon University. Mostly rewritten as a result of experience from early deployments, Andrew had four major software components: ASUS X53S Keyboard

The Andrew User Interface System

After IBM's funding ended, Andrew continued as an open source project named the Andrew User Interface System. AUIS is a set of tools that allows users to create and distribute documents containing a variety of formatted and embedded objects. It is an open-source project run at the Department of Computer Science at CMU. The Andrew Consortium governs and maintains the development and distribution of the Andrew User Interface System.[5]HP Pavilion G60-230 Keyboard The Andrew User Interface System encompasses three primary components. The Andrew User Environment (AUE) contains the main editor, help system, user interface, and tools for rendering multimedia and embedded objects. The Andrew Toolkit (ATK) contains all of the formattable and embeddable objects, and allows a method for developers to design their own objects. TOSHIBA Satellite L775D-S7332 Keyboard ATK allows for multi-level object embedding, in which objects can be embedded in one another. For example, a raster image object can be embedded into a spreadsheet object. The Andrew Message System (AMS) provides a mail and bulletin board access, which allows the user to send, receive, and organize mail as well as post and read from message boards. HP Pavilion dv6-3178ee Keyboard M computer From Wikipedia, the free encyclopedia 3M was a goal first proposed in the early 1980s by Raj Reddy and his colleagues at Carnegie Mellon University (CMU) as a minimum specification for academic/technical workstations: at least a megabyte of memory, a megapixel display and a million instructions per second (MIPS) processing power.[1] It was also often said that it should cost no more than a "megapenny" ($10,000). HP AEAT8TPU319 Keyboard This was in contrast to the personal computers of that period, such as the IBM Personal Computer which might have 64KB memory, a 320×200 pixel display (64000 pixels), and 30 kiloFLOPS floating point performance. HP Pavilion G6-1B59WM Keyboard The concept was inspired by the Xerox Alto which had been designed in the 1970s at the Xerox Palo Alto Research Center. Several Altos were donated to CMU, Stanford, and MIT in 1979. An early 3M computer was the PERQ Workstation made by Three Rivers Computer Corporation.[2] The PERQ had a 1 million P-codes (Pascalinstructions) per second processor, HP G42-386TX Laptop Keyboard 256 KB of RAM (upgradeable to 1 MB), and a 768×1024 pixel display on a 15 inches (380 mm) display. While not quite a true 3M machine, it was used as the initial 3M machine for the CMU Scientific Personal Integrated Computing Environment (SPICE) workstation project. HP Pavilion dv6-3117sl Laptop Keyboard The Stanford University Network SUN workstation, designed by Andy Bechtolsheim in 1980, is another example. It was then commercialized by Sun Microsystems in 1982. Apollo Computer (in the Route 128 region) announced the Apollo/Domain computer in 1981.[3] The first "megapenny" 3M workstation was the Sun-2/50 diskless desktop workstation with a list price of $8,900 in 1986. TOSHIBA NSK-T4N01 Laptop Keyboard The original NeXT Computer was introduced in 1988 as a 3M machine by Steve Jobs, who first heard this term at Brown University.[4] Its so-called "MegaPixel" display had just over 930,000 pixels with four shades of gray. However, floating point performance was only about .25 megaflops. SONY Vaio PCG-K35 Laptop Keyboard The Xerox Alto was one of the first computers designed for individual use (though not as a home computer), making it arguably what is now called a personal computer. It was developed at Xerox PARC in 1973. It was the first computer to use the desktop metaphor and mouse-driven graphical user interface (GUI). DELL Latitude E5500 Keyboard It was not a commercial product, but several thousand units were built and were heavily used at PARC, other Xerox facilities, and at several universities for many years. The Alto greatly influenced the design of personal computers in the following decades, notably the Apple Macintosh and the first Sun workstations. It is now rare and a valued collector's item.[1]Lenovo ThinkPad T410-2522 Keyboard


The Alto was conceived in 1972 in a memo written by Butler Lampson, inspired by the On-Line System (NLS) developed byDouglas Engelbart at SRI, and was designed primarily by Chuck Thacker. Industrial Design and manufacturing was sub-contracted to Clement Designlabs, whose team included Carl J. IBM Lenovo ThinkPad R50 2889 Keyboard Clement, Ken Campbell (mechanical engineer), Terry West (industrial designer), and Fred Stengel.[2] An initial run of 80 units was produced by Clement Designlabs, working with Doug Fairbairn at Xerox PARC, Tony Ciuffini and Rick Nevinger at Xerox El Segundo, who were responsible for installing the Alto’s electronics. Due to the success of the pilot run, the team went on to produce approximately 2000 units over the next ten years.[2]DELL Inspiron N4050 Keyboard Several Xerox Alto chassis are now on display at the Computer History Museum in Mountain View, California, and a running system is on display at the Living Computer Museum in Seattle, FUJITSU Lifebook S7111 Keyboard Washington. For his pioneering design and realization of the Alto, Charles P. Thacker was awarded the 2009 Turing Award of the Association for Computing Machinery on March 9, 2010.[3] The 2004 Charles Stark Draper Prize was awarded to Thacker, Alan C. Kay, Butler Lampson, and Robert W. Taylor for their work on Alto.[4]TOSHIBA Satellite L755-S5364 Keyboard Architecture The following description is based primarily on the August 1976 Alto Hardware Manual by Xerox PARC. Alto was a microcoded design but, unlike many computers, the microcode engine was not hidden from the programmer in a layered design. Applications such as Pinball took advantage of this to accelerate performance. The Alto had a bit-slice arithmetic logic unit (ALU) based on the Texas Instruments' 74181 chip, DELL Inspiron 1545 Keyboard a ROM control store with a writable control store extension and had 128 (expandable to 512) kB of main memory organized in 16-bit words. Mass storage was provided by a hard disk that used a removable 2.5 MB single-platter cartridge (Diablo Systems, a company Xerox later bought) similar to those used by the IBM 2310. The base machine and one disk were housed in a cabinet about the size of a small refrigerator; one additional disk could be added in daisy-chain fashion. TOSHIBA Satellite L755-S5364 Keyboard Alto both blurred and ignored the lines between functional elements. Rather than a distinct central processing unit with a well-defined electrical interface (e.g., system bus) to storage and peripherals, the Alto ALU interacted directly with hardware interfaces to memory and peripherals, driven by microinstructionsoutput from the control store. TOSHIBA Satellite L775D-S7330 Keyboard The microcode machine supported up to 16 cooperative tasks, each with fixed priority. The emulator task executed the normal instruction set to which most applications were written (which was rather like that of a Data General Nova). Others tasks served the display, memory refresh, disk, network, and other I/O functions. DELL Latitude D600 Keyboard As an example, the bitmap display controller was little more than a 16-bit shift register; microcode moved display refresh data from main memory to the shift register, which serialized it into a display of pixels corresponding to the ones and zeros of the memory data. Ethernet was likewise supported by minimal hardware, SONY VAIO VGN-CR31S Keyboard with a shift register that acted bidirectionally to serialize output words and deserialize input words. Its speed was limited to 3 Mbit/s because the microcode engine could not go faster and continue to support the video display, disk activity and memory refresh. HP 317443-001 Keyboard Unlike most minicomputers of the era, Alto did not support a serial terminal for user interface. Apart from an Ethernet connection, the Alto's only common output device was a bi-level (black and white) cathode ray tube (CRT) display with a tilt-and-swivel base, HP Mini 210-2006sa Keyboard mounted in "portrait" orientation rather than the more common "landscape" orientation. Its input devices were a custom detachable keyboard, a three-button mouse, and an optional 5-key chord keyset. The last two items had been introduced by SRI's On-Line System; while the mouse was an instant success among Alto users, the chord keyset never became popular. HP Mini 210-2006sa Keyboard In the early mice, the buttons were three narrow bars, arranged top to bottom rather than side to side; they were named after their colors in the documentation. The motion was sensed by two wheels perpendicular to each other. These were soon replaced with ball-type mice, which were invented by Bill English. These were photo-mechanical mice — first using white light and then using IR to count the rotations of wheels inside the mouse. HP Pavilion DV6-1022el Keyboard The keyboard was interesting in that each key was represented as a separate bit in a set of memory locations. As a result, it was possible to read multiple key presses simultaneously. This characteristic was used to alter where the Alto would boot from. The keyboard value was used as the sector address on the disk to boot from, Compaq Presario CQ57 Series Keyboard and by holding specific keys down while pressing the boot button, different microcode and operating systems could be loaded. This gave rise to the expression "nose boot" where the keys needed to boot for a test OS release required more fingers than you could come up with. Nose boots were made obsolete by the "move2keys" program that shifted files on the disk so that a specified key sequence could be used. HP Pavilion dm3-1020CA Keyboard Several other I/O devices were developed for the Alto, including a TV camera, the Hy-Type daisywheel printer and a parallel port, although these were quite rare. The Alto could also control external disk drives to act as a file server. This was a common application for the machine. ACER Aspire 5742 Keyboard

Diffusion and evolution

Technically, the Alto was a small minicomputer, but it could be considered a personal computer in the sense that it was used by a single person sitting at a desk, in contrast with the mainframes and other minicomputers of the era. It was arguably "the first personal computer", although this title is disputed by others.[5]HP Pavilion DV7-3065dx Keyboard The Alto was never a commercial product, although over two thousand were built. Universities, including MIT, Stanford, CMU, and the University of Rochester received donations of Altos including IFS file servers and Dover laser printers. FUJITSU Amilo Mini Ui 3520 Keyboard These machines were the inspiration for the ETH Zürich Lilith and Three Rivers Company PERQ workstations, and the Stanford University Network (SUN) workstation, which was eventually marketed by a spin-off company, Sun Microsystems. TheApollo/Domain workstation was heavily influenced by the Alto. SONY VAIO VGN-AR170 Keyboard The White House information systems department acquired an Alto, and sought to lead Federal computer suppliers in its direction. The Executive Office of the President of the United States (EOP) issued a request for proposal for a computer system to replace the aging Office of Management and Budget (OMB) budget system, using Alto-like workstations, connected to an IBM-compatible mainframe. The request was eventually withdrawn because no mainframe producer could supply such a configuration. HP pavilion DV7-1000 Keyboard In December 1979, Apple Computer's co-founder Steve Jobs visited Xerox PARC, where he was shown the Smalltalk-80 programming environment, networking, and most importantly the WYSIWYG, mouse-driven graphical user interface provided by the Alto. He reportedly was not impressed by the first two, but was excited by the last one, and promptly integrated it, first into the Lisa and then in the Macintosh, attracting several key researchers to work in his company.[6]Compaq Presario CQ57 Series Keyboard In 1980–1981, Xerox Altos were used by engineers at PARC and at the Xerox System Development Department to design the Xerox Star workstations. SONY NSK-S8101 Keyboard Xerox itself was slow to realize the value of the technology that had been developed at PARC.[7] After their unhappy experience with Scientific Data Systems (SDS, later XDS) in the late 1960s, the firm was reluctant to get into the computer business again with commercially untested designs. ASUS X53S Keyboard Before the advent of personal computers such as the Apple II and the IBM Personal Computer (IBM PC), the computer market was dominated by costly mainframes and minicomputers equipped with dumb terminals that time-shared processing time of the central computer. So through the 1970s Xerox showed no interest in the work done at PARC. When Xerox finally entered the PC market with the Xerox 820, they pointedly rejected the Alto design and opted instead for a very conventional model, a CP/M-based machine with the then-standard 80 by 24 character-only monitor and no mouse. ACER Aspire 5742 Keyboard With the help of PARC researchers, Xerox eventually developed the Xerox Star (and later the cost reduced Star; the 6085) office system, which included the Dandelion and Daybreak workstations. These machines, based on the 'Wildflower' architecture described in a paper by Butler Lampson, incorporated most of the Alto innovations, including the graphical user interfacewith icons, windows, folders, Ethernet-based local networking, and network-based laser printer services. HP Pavilion DV6-1007tx Keyboard Xerox only realized their mistake in the early 1980s, after Apple's Macintosh revolutionized the PC market via its bitmap display and the mouse-centered interface—both copied from the Alto.[7] While the Xerox Star series was a relative commercial success, it came too late. The expensive Xerox workstations could not compete against the cheaper GUI-based workstations that appeared in the wake of the first Macintosh, and Xerox eventually quit the workstation market for good. HP pavilion DV7-1000 Keyboard In computing, the desktop metaphor is an interface metaphor which is a set of unifying concepts used by graphical user interfaces to help users more easily interact with the computer.[1] The desktop metaphor treats the computer monitor as if it is the user's desktop, upon which objects such as documents and folders of documents can be placed. TOSHIBA PK130260100 Keyboard A document can be opened into a window, which represents a paper copy of the document placed on the desktop. Small applications called desk accessories are also available, such as a desk calculator or notepad, etc. DELL NSK-D8001 Keyboard The desktop metaphor itself has been extended and stretched with various implementations of desktop environments, since access to features and usability of the computer are usually more important than maintaining the ‘purity’ of the metaphor. Hence we find trash cans on the desktop, as well as disks and network volumes (which can be thought of as filing cabinets—not something normally found on a desktop). Other features such as menu bars, task bars, or docks have no counterpart on a real-world desktop. HP pavilion DV7-1000 Keyboard The desktop metaphor was first introduced by Alan Kay at Xerox PARC in 1970 and elaborated in a series of innovative software applications developed by PARC scientists throughout the ensuing decade. The first commercial computer that adopted this kind of interface was the Xerox Star. ACER Aspire One D150-1920 Keyboard One of the very first desktop-like interfaces on the market was a program called Magic Desk I built on a cartridge for theCommodore 64 home computer in 1983. A very primitive GUI presented a low resolution sketch of a desktop, complete with telephone, drawers, calculator, etc. The user made his choices by moving a sprite depicting a hand pointing by using the samejoystick SONY VGN-FE31M Keyboard the user may have used for video gaming. Onscreen options were chosen by pushing the fire button on the joystick. The Magic Desk program featured a typewriter graphically emulated complete with audio effects. Other applications included a calculator, rolodex organiser, and a terminal emulator. Files could be archived into the drawers of the desktop. A trashcanwas also present. HP Pavilion dv6-2113sa Keyboard The first computer to popularise the desktop metaphor, using it as a standard feature over the earlier command line interfacewas the Apple Macintosh in 1984. The desktop metaphor is ubiquitous in modern-day personal computing; it is found in mostdesktop environments of modern operating systems: Windows as well as Mac OS X, Linux, and other Unix-like systems. Lenovo ThinkPad Edge E520 Keyboard BeOS observed the desktop metaphor more strictly than many systems. For example, external hard drives appeared on the ‘desktop’, while internal ones were accessed clicking on an icon representing the computer itself. By comparison, the Mac OS places all drives on the desktop itself by default, while in Windows the user can access the drives through an icon labelled "Computer".DELL Inspiron 1564 Keyboard Amiga terminology for its desktop metaphor was taken directly from workshop jargon. The desktop was called Workbench, programs were called tools, SONY VAIO VGN-CR160F Keyboard small applications (applets) were utilities, directories were drawers, etc. Icons of objects were animated and the directories are shown as drawers which were represented either open or closed. As in the Mac OS desktop, an icon for a floppy disk or CD-ROM would appear on the desktop when the disk was inserted into the drive, as it was a virtual counterpart of a physical floppy disk or CD-ROM on the surface of a workbench. SONY VAIO VGN-CR31S Keyboard

Paper paradigm

The paper paradigm refers to the paradigm used by most modern computers and operating systems. The paper paradigm consists of, usually, black text on a white background, files within folders, and a "desktop." The paper paradigm was created by many individuals and organisations, such as Douglas Engelbart, ASUS F8Sp Keyboard Xerox PARC, and Apple Computer, and was an attempt to make computers more user-friendly by making them resemble the common workplace of the time (with papers, folders, and a desktop).[2] It was first presented to the public by Engelbart in 1968, in what is now referred to as "The Mother of All Demos".ACER Aspire 5536 Keyboard From John Siracusa:[3] Back in 1984, explanations of the original Mac interface to users who had never seen a GUI before inevitably included an explanation of icons that went something like this: "This icon represents your file on disk." But to the surprise of many, users very quickly discarded any semblance of indirection. HP Probook 4515S Keyboard This icon is my file. My file is this icon. One is not a "representation of" or an "interface to" the other. Such relationships were foreign to most people, and constituted unnecessary mental baggage when there was a much more simple and direct connection to what they knew of reality. SAMSUNG R470 Keyboard Since then, many aspects of computers have wandered away from the paper paradigm by implementing features such as "shortcuts" to files, hypertext, and non-spatial file browsing. A shortcut (a link to a file that acts as a redirecting proxy, not the actual file) and hypertext have no real-world equivalent. Non-spatial file browsing, HP G62-b25SA Keyboard as well, may confuse novice users, as they can often have more than one window representing the same folder open at the same time, something that is impossible in reality. These and other departures from real-world equivalents are violations of the pure paper paradigm. HP G42-359TU Keyboard Usability is the ease of use and learnability of a human-made object. The object of use can be a software application, website, book, tool, machine, process, or anything a human interacts with. A usability study may be conducted as a primary job function by a usability analyst or as a secondary job function bydesigners, technical writers, TOSHIBA NSK-TBD01 Keyboard marketing personnel, and others. It is widely used in consumer electronics, communication, and knowledge transfer objects (such as a cookbook, a document or online help) and mechanical objects such as a door handle or a hammer. HP G61-110SA Keyboard Usability includes methods of measuring usability, such as needs analysis[1] and the study of the principles behind an object's perceived efficiency or elegance. In human-computer interaction and computer science, usability studies the elegance and clarity with which the interaction with a computer program or a web site (web usability) is designed. Usability differs from user satisfaction insofar as the former also embraces usefulness (see Computer user satisfaction). HP Pavilion dv6-2114sa Keyboard Complex computer systems find their way into everyday life,

and at the same time the market is saturated with competing brands. This has made usability more popular and widely recognized in recent years, as companies see the benefits of researching and developing their products with user-oriented methods instead oftechnology-oriented methods. Dell Latitude D400 Keyboard By understanding and researching the interaction between product and user, the usability expert can also provide insight that is unattainable by traditional company-oriented market research. For example, after observing and interviewing users, the usability expert may identify needed functionality or design flaws that were not anticipated. A method called contextual inquiry does this in the naturally occurring context of the users own environment. SAMSUNG R522 Keyboard In the user-centered design paradigm, the product is designed with its intended users in mind at all times. In the user-driven or participatory design paradigm, some of the users become actual or de facto members of the design team.[2]TOSHIBA NB100-11B Keyboard The term user friendly is often used as a synonym for usable, though it may also refer to accessibility. Usability describes the quality of user experience across websites, software, products, and environments. IBM Lenovo ThinkPad X300 Keyboard There is no consensus about the relation of the terms ergonomics (or human factors) and usability. Some think of usability as the software specialization of the larger topic of ergonomics. Others view these topics as tangential, with ergonomics focusing on physiological matters (e.g., turning a door handle) and usability focusing on psychological matters (e.g., recognizing that a door can be opened by turning its handle). HP Pavilion dv6-2108ea Keyboard Usability is also important in website development (web usability). According to Jakob Nielsen, "Studies of user behavior on the Web find a low tolerance for difficult designs or slow sites. SONY Vaio PCG-K215S Keyboard People don't want to wait. And they don't want to learn how to use a home page. There's no such thing as a training class or a manual for a Web site. People have to be able to grasp the functioning of the site immediately after scanning the home page—for a few seconds at most."[3]Otherwise, most casual users simply leave the site and browse or shop elsewhere. ACER Aspire 7520 Keyboard Definition Usability is often associated with the functionalities of the product (cf. ISO definition, below), in addition to being solely a characteristic of the user interface (cf. framework of system acceptability, also below, which separates usefulness into utility and usability). For example, in the context of mainstream consumer products, an automobile lacking a reverse gear could be considered unusable according to the former view, and lacking in utility according to the latter view. COMPAQ Presario C700 Keyboard When evaluating user interfaces for usability, the definition can be as simple as "the perception of a target user of the effectiveness (fit for purpose) and efficiency (work or time required to use) of the Interface". Each component may be measured subjectively against criteria, e.g., Principles of User Interface Design, to provide a metric, often expressed as a percentage. ACER Aspire 5742 Keyboard It is important to distinguish between usability testing and usability engineering. Usability testing is the measurement of ease of use of a product or piece of software. In contrast, usability engineering (UE) is the research and design process that ensures a product with good usability. IBM Thinkpad T61P Keyboard Usability is a non-functional requirement. As with other non-functional requirements, usability cannot be directly measured but must be quantified by means of indirect measures or attributes such as, for example, the number of reported problems with ease-of-use of a system. SONY Vaio PCG-K215S Keyboard

Intuitive interfaces

The term intuitive is often listed as a desirable trait in usable interfaces, often used as a synonym for learnable. Some experts such as Jef Raskin have discouraged using this term in user interface design, claiming that easy to use interfaces are often easy because of the user's exposure to previous similar systems, HP 597635-001 Keyboard thus the term 'familiar' should be preferred.[5] As an example: Two vertical lines "||" on media player buttons do not intuitively mean "pause"—they do so by convention. Aiming for "intuitive" interfaces (based on reusing existing skills with interaction systems) could lead designers to discard a better design solution only because it would require a novel approach. TOSHIBA NB200 Keyboard This position is sometimes illustrated with the remark that "The only intuitive interface is the nipple; everything else is learned."[6] Bruce Tognazzini even denies the existence of "intuitive" interfaces, since such interfaces must be able to intuit, i.e., "perceive the patterns of the user's behavior and draw inferences."[7] Instead, he advocates the term "intuitable," i.e., "that users could intuit the workings of an application by seeing it and using it." He continues, however, "But even that is a less than useful goal since only 25 percent of the population depends on intuition to perceive anything." HP 605344-001 Keyboard

ISO/TR 16982:2002

ISO/TR 16982:2002 ("Ergonomics of human-system interaction—Usability methods supporting human-centered design") is a standard that provides information on human-centred usability methods that can be used for design and evaluation. It details the advantages, disadvantages, and other factors relevant to using each usability method. It explains the implications of the stage of the life cycle and the individual project characteristics for the selection of usability methods and provides examples of usability methods in context. HP 646568-001 Keyboard The main users of ISO/TR 16982:2002 are project managers. It therefore addresses technical human factors and ergonomics issues only to the extent necessary to allow managers to understand their relevance and importance in the design process as a whole. The guidance in ISO/TR 16982:2002 can be tailored for specific design situations by using the lists of issues characterizing the context of use of the product to be delivered. SONY VAIO VGN-FS215B Keyboard Selection of appropriate usability methods should also take account of the relevant life-cycle process. ISO/TR 16982:2002 is restricted to methods that are widely used by usability specialists and project managers. It does not specify the details of how to implement or carry out the usability methods described. TOSHIBA Satellite C655-S9531D Keyboard ISO 9241 is a multi-part standard that covers a number of aspects of people working with computers. Although originally titled Ergonomic requirements for office work with visual display terminals (VDTs), it has been retitled to the more generic Ergonomics of Human System Interaction. HP Pavilion DV6-1210sa Keyboard As part of this change, ISO is renumbering the standard so that it can include many more topics. The first part to be renumbered was part 10 (now renumbered to part 110). Part 1 is a general introduction to the rest of the standard. Part 2 addresses task design for working with computer systems. Parts 3–9 deal with physical characteristics of computer equipment. TOSHIBA NB200-00C Keyboard DELL Inspiron 9300 Keyboard Parts 110 and parts 11–19 deal with usability aspects of software, including Part 110 (a general set of usability heuristics for the design of different types of dialogue) and Part 11 (general guidance on the specification and measurement of usability). APPLE A1278 Keyboard The design team should be user driven and in direct contact with potential users. Several evaluation methods, including personas, cognitive modeling, inspection, inquiry, prototyping, and testing methods may contribute to understanding potential users. HP Mini 210-2030ez Keyboard Usability considerations such as who the users are and their experience with similar systems must be examined. As part of understanding users, this knowledge must “...be played against the tasks that the users will be expected to perform.”[9]HP Pavilion dv6-3125sa Keyboard This includes the analysis of what tasks the users will perform, which are most important, and what decisions the users will make while using your system. Designers must understand how cognitive and emotional characteristics of users will relate to a proposed system. HP Pavilion dv5-1126ee Keyboard One way to stress the importance of these issues in the designers’ minds is to use personas, which are made-up representative users. See below for further discussion of personas. Another more expensive but more insightful method is to have a panel of potential users work closely with the design team from the early stages.[10]HP 640208-001 Keyboard

Iterative design

Iterative design is a design methodology based on a cyclic process of prototyping, testing, analyzing, and refining a product or process. Based on the results of testing the most recent iteration of a design, changes and refinements are made. This process is intended to ultimately improve the quality and functionality of a design. In iterative design, HP Pavilion zd7040ea Keyboard interaction with the designed system is used as a form of research for informing and evolving a project, as successive versions, or iterations of a design are implemented. The key requirements for Iterative Design are: identification of required changes, an ability to make changes, and a willingness to make changes. ACER Aspire 5336 Keyboard When a problem is encountered, there is no set method to determine the correct solution. Rather, there are empirical methods that can be used during system development or after the system is delivered, usually a more inopportune time. Ultimately, iterative design works towards meeting goals such as making the system user friendly, easy to use, easy to operate, simple, etc.[10]FUJITSU Lifebook E8310 Keyboard HP 550 Keyboard Heuristic evaluation is a usability engineering method for finding and assessing usability problems in a user interface design as part of an iterative design process. It involves having a small set of evaluators examining the interface and using recognized usability principles (the "heuristics"). It is the most popular of the usability inspection methods, as it is quick, cheap, and easy. SONY VAIO PCG-FR315M Keyboard Heuristic evaluation was developed to aid in the design of computer user-interface design. It relies on expert reviewers to discover usability problems and then categorize and rate them by a set of principles (heuristics.) It is widely used based on its speed and cost-effectiveness. Jakob Nielsen's list of ten heuristics is the most commonly used in industry. These are ten general principles for user interface design. They are called "heuristics" because they are more in the nature of rules of thumb than specific usability guidelines. IBM Lenovo Thinkpad X201 Keyboard Meta-Analysis is a statistical procedure to combine results across studies to integrate the findings. This phrase was coined in 1976 as a quantitativeliterature review. This type of evaluation is very powerful for determining the usability of a device because it combines multiple studies to provide very accurate quantitative support. SONY VAIO PCG-FR315M Keyboard Persona Personas are fictitious characters created to represent a site or product's different user types and their associated demographics and technographics. Alan Cooper introduced the concept of using personas as a part of interactive design in 1998 in his book The Inmates Are Running the Asylum,[14] but had used this concept since as early as 1975. HP Pavilion G6-1C58DX Keyboard Personas are a usability evaluation method that can be used at various design stages. The most typical time to create personas is at the beginning of designing so that designers have a tangible idea of who the users of their product will be. Personas are the archetypes that represent actual groups of users and their needs, FUJITSU Amilo Mini Ui 3520 Keyboard which can be a general description of person, context, or usage scenario. This technique turns marketing data on target user population into a few physical concepts of users to create empathy among the design team, with the final aim of tailoring a product more closely to how the personas will use it. TOSHIBA Satellite P300 Keyboard To gather the marketing data that personas require, several tools can be used, including online surveys, web analytics, customer feedback forms, and usability tests, and interviews with customer-service representatives.[15]HP 597635-001 Keyboard


While conducting usability tests, designers must use usability metrics to identify what it is they are going to measure, or the usability metrics. These metrics are often variable, and change in conjunction with the scope and goals of the project. The number of subjects being tested can also affect usability metrics, HP 550 Keyboard as it is often easier to focus on specific demographics. Qualitative design phases, such as general usability (can the task be accomplished?), and user satisfaction are also typically done with smaller groups of subjects.[17] Using inexpensive prototypes on small user groups provides more detailed information, because of the more interactive atmosphere, and the designer's ability to focus more on the individual user. FUJITSU CP253873-XX Keyboard As the designs become more complex, the testing must become more formalized. Testing equipment will become more sophisticated and testing metrics become more quantitative. With a more refined prototype, designers often test effectiveness, efficiency, and subjective satisfaction, by asking the user to complete various tasks. IBM Lenovo Thinkpad X201 Keyboard These categories are measured by the percent that complete the task, how long it takes to complete the tasks, ratios of success to failure to complete the task, time spent on errors, the number of errors, rating scale of satisfactions, number of times user seems frustrated, etc.[18] HP Pavilion dv4t-1300 CTO Keyboard Additional observations of the users give designers insight on navigation difficulties, controls, conceptual models, etc. The ultimate goal of analyzing these metrics is to find/create a prototype design that users like and use to successfully perform given tasks.[16]ACER ZU2 Keyboard After conducting usability tests, it is important for a designer to record what was observed, in addition to why such behavior occurred and modify the model according to the results. Often it is quite difficult to distinguish the source of the design errors, and what the user did wrong. However, effective usability tests will not generate a solution to the problems, but provide modified design guidelines for continued testing. Lenovo 3000 G530 4151 Keyboard Usability practitioners are sometimes trained as industrial engineers, psychologists, kinesiologists, systems design engineers, or with a degree in information architecture, information or library science, SONY 147996611 Keyboard or Human-Computer Interaction (HCI). More often though they are people who are trained in specific applied fields who have taken on a usability focus within their organization. Anyone who aims to make tools easier to use and more effective for their desired function within the context of work or everyday living can benefit from studying usability principles and guidelines. DELL Vostro 1015 Keyboard For those seeking to extend their training, the Usability Professionals' Association offers online resources, reference lists, courses, conferences, and local chapter meetings. The UPA also sponsors World Usability Day each November.[23]ASUS Z91E Keyboard Related professional organizations include the Human Factors and Ergonomics Society (HFES) and the Association for Computing Machinery's special interest groups in Computer Human Interaction (SIGCHI), and Computer Graphics and Interactive Techniques (SIGGRAPH). ACER Aspire 5552 Keyboard The Society for Technical Communication also has a special interest group on Usability and User Experience (UUX). They publish a quarterly newsletter calledUsability Interface.[24]SONY VGN-FE11H Keyboard By working to improve said factors, corporations can achieve their goals of increased output at lower costs, while potentially creating optimal levels of customer satisfaction. There are numerous reasons why each of these factors correlates to overall improvement. For example, making a piece of software’s user interface easier to understand would reduce the need for extensive training. ASUS A6M Keyboard The improved interface would also tend to lower the time needed to perform necessary tasks, and so would both raise the productivity levels for employees and reduce development time (and thus costs). It is important to note that each of the aforementioned factors are not mutually exclusive, rather should be understood to work in conjunction to form the overall workplace environment. HP G61 Keyboard HP Probook 4710S Keyboard HP G42-364LA Keyboard ASUS F82Q Keyboard

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upvc windows 27/08/2012 08:04

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