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The Xerox Star: A Retrospective. Presented by: Yang Wang Michal Shmueli-Scheuer. This presentation is mainly based on:. “The Xerox Star: A Retrospective” - Jeff Johnson, Teresa L. Roberts (US West Advanced Tech) - William Verplank (IDTwo) - David C. Smith (Cognition, Inc.)
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The Xerox Star: A Retrospective Presented by: Yang Wang Michal Shmueli-Scheuer
This presentation is mainly based on: “The Xerox Star: A Retrospective” - Jeff Johnson, Teresa L. Roberts (US West Advanced Tech) - William Verplank (IDTwo) - David C. Smith (Cognition, Inc.) - Charles H. Irby, Marian Beard (Metaphor Com. Sys.) - Kevin Mackey (Xerox)
A bird’s-eye view of this presentation Part I: What is Star? - Brief introduction - Distinctive features Part II: History of Star development - Pre-Xerox, Star, and ViewPoint - Lessons from experience
Brief introduction • Xerox introduced the 8010 “Star” Information system in April of 1981. • Star was designed as an office automation system where users would produce, retrieve, distribute, and organize documentation, presentations, memos, and reports.
Assumptions & goals • Assumption 1: Users are only interested in getting their work done and not at all interested in computers. • Goal 1: To make the “computer” as invisible to users as possible.
Assumptions & goals (Cont.) • Assumption 2: Star’s users would be casual, occasional users rather than people who spent most of their time at the machine. • Goal 2: Star should be easy to learn and remember.
Star’s features • Machine and network level • Window and file manager level • User interface level • Document editor level
Star’s features • Machine and network level • Window and file manager level • User interface level • Document editor level
Machine and network level • Star was designed primarily to operate in a distributed computing environment. • All personal workstations would be connected via Ethernet and would share access to file servers, printers.. • Use 2-button mouse
Star’s features • Machine and network level • Window and file manager level • User interface level • Document editor level
Window and file manager level • Windows: • Star allowed several programs to display information simultaneously in separate windows. • Windows don’t overlap because early testing showed that users spent a lot of time adjusting windows. • Integrated applications: • Text, graphics, tables, and mathematical formulas are all edited inside documents. • Star was not fully integrated in this sense.
Star’s features • Machine and network level • Window and file manager level • User interface level • Document editor level
User interface level • Desktop Metaphor • Generic Commands • Direct Manipulation and Graphical User Interface • Icons and Iconic File Management • Few Modes • Objects have properties • Progressive Disclosure • Consistency • Emphasis on Good Graphic and Screen Design
Desktop Metaphor • Resembles the top of an office desk, together with surrounding furniture and equipment. • The system associates different types of data files with appropriate programs, so users mainly deal with data files instead of programs. • Example: - users “open a document”, rather than “invoke a text editor” • Make the system easy to learn and use
Generic Commands • A small set of generic commands simplifies the system. • Generic commands apply to all types of data, and each type of data object interprets a generic command in a way appropriate for it. • Examples: move, copy, open…
Direct Manipulation & Graphical User Interface • Assumption: casual users • Design philosophy: • Recognition > Recall • Seeing and Pointing > Remembering and Typing • User control the system by manipulating graphic elements on the screen. • Make the users easier to learn and use Star.
Icons and Iconic File Management • Icons: pictures of office objects • Data files are represented by icons • Each type of file has a characteristic icon representation • Allow users to organize files spatially rather than by distinctive naming. • Example: • Files can be kept together by putting them into a folder
Few Modes • A system has modes if user actions differ in effects or availability in different situations • “Modes in interactive computer systems are undesirable because they restrict the functions available at any given point and force the user to keep track of the system’s state to know what effect their actions will have…” ---Tesler • Star’s approaches to avoid modes: • Extensive use of generic commands • Allow applications to operate simultaneously
Objects have properties • Properties allow objects of the same type to vary in appearance, layout and behavior. • In Star, properties are displayed and changed in graphic forms called property sheets.
Progressive Disclosure • Detail is hidden from users until they ask or need to see it • To avoid overwhelming users with information • Star provides default settings and hides settings that users are unlikely to change • Example: in property sheets
Consistency • Star and all its applications were designed and developed in a unified way by a single development group. • Star achieved a high degree of consistency. • Example: • The left button of mouse always selects. • The right button of mouse always extends the selection.
Emphasis on Good Graphic and Screen Design • Windows, icons, and property sheets are useless if user cannot easily distinguish them from the background or each other… • Xerox hired graphic designers to determine the appearance and placement of objects • Some principals applied: • The illusion of manipulable objects (e.g. scrolling window) • Visual order and user focus …
In Star, the icon selected by the user is indicated by inverting the image Still popular Visual order and user focus
Star’s features • Machine and network level • Window and file manager level • User interface level • Document editor level
Document editor level • WYSIWYG (what you see is what you get) • Star documents are displayed as they will print • Extended character set for multilingual capability • The document editor is supposedly the primary application, thus most applications are integrated into the document editor.
Memex Simula Reactive Engine NLS Sketchpad Alto Bravo SRI Smalltalk SIL Draw Flyer Markup Press Gypsy Office Talk BravoX Pymalion Mess Interpress Doodle Tajo Star (8010) Lisa Augment Cedar Deluxe paint Macintosh ViewPoint (6085) interleaf Postscript Metaphor workstation Cognition MCAE system Mac II ViewPoint 2.0
Memex- 1945 • Vannevar Bush • Aswe may think…. After 18 years….
Sketchpad- 1963 • Ivan Sutherland • Interactive graphic system • Create graphical figures on a 9 inch CRT display using a light pen • Geometric shapes as Objects: move, copy, rotate..
Invent the mouse NLS- 1960’s • Douglas Engelbart • Compare different devices: light pen, track ball, joysticks, the "Graficon“ and Knee brace
NLS- 1960’s • CRT display • Full screen oriented • MOUSE • First system to organize textual and graphical information in trees and networks.
Smalltalk- 1971 • Alan Kay • “children should program in Smalltalk” • Smalltalk relied heavily on graphics, animation, mouse driven input, windows and simultaneous applications. Fact: The Star wasn’t written in Smalltalk !
Xerox PARC- 1970 • Palo Alto Research Center was established in order to explore technologies • Expansion into the office systems business. • Personal computer in a distributed environment • ALTO: • 2.5 MB HD, 256KB Memory, bitmapped display, 50KB of display memory and a mouse. • Became operational 1972
Xerox PARC- 1970 • Ethernet, 1973 • Bob Metcalfe • Standardized layered communications protocol • Provided a way of connecting computers much more flexibly than previously possible. • Soon after the first Altos were built, they were networked together.
Pygmalion- 1975 • David C. Smith • The first large program to be written in Smalltalk • Programming can be accomplished by interacting with graphical elements on a screen. • Computers can be programmed in the language of the user interface • By demonstrating what you want done and having the computer remember and reproduce it. Fact: The idea of using icons came mainly from Pygmalion !
Text editor • Gypsy- text editor • BravoX- led to Microsoft Word. • Draw- graphical object editor • Markup- bitmap graphics editor (paint program) Graphic editor • Laser printing- press page-description language (Adobe, postscript) • Laurel and Hardy- electronic mail • Officetalk- prototype office automation system (tracking…) Different utilities Other software's for Alto • Bravo- advanced document editing system WYSIWYG, underline, boldface, italic, font, size..
Star (Xerox 8010)- 1981 • To develop Star, Xerox created the Systems Development Department (SDD) • SDD was split between two locations: El Segundo (So. Cal) and Palo Alto (No. Cal): • El Segundo did most of the implementation • Palo Alto did most of the design and prototyping • Mesa, a dialect of Pascal, was the primary product programming language used • The hardware was designed in conjunction with the software
Star (Xerox 8010)- 1981 • Hardware: • 384KB- 1.5MB Memory, HD 40MB, 17 inch display, 8 inch floppy disk a mouse and Ethernet. • Software: • Uniformity of specifications, uniform design • Strict format- Objects and Actions • Objects- applications and system features • Actions- actions that the software provide for manipulating the objects. • Cost- starting from $16,500
Problems…. • The star didn’t sale as expected. • Performance, extensibility, maintainability, cost… • It was monolithic: • The system knew about all applications, and all parts of the system knew about all other parts. It was difficult to correct problems, add new features and increase performance. • The monolithic architecture did not lend itself to distributed, multiparty development. • Star’s infrastructure was rewritten according to more flexible model- ViewPoint
Lessons from experience • Pay attention to industry trends: • PARC researchers and Star’s designers didn’t pay enough attention to the “other” personal computer revolution occurring outside of Xerox. • Release new technologies to public- become a standard. • Pay attention to what customers want: • Star should have been designed from the start to be open and extensible by users, as the Alto was. Star didn’t have the functionality customers wanted.
Lessons from experience • Know your competition: • The price of a star’s workstation was too high to compete with other microcomputer-based PC • Avoid geographically split development organizations: • The implementers didn’t benefit from much of the prototyping done as PARC. • Lack of shared background
The best way to predict the future is to invent it.. [Alan Kay]