The Xerox Star A Retrospective Presented by Liang
The Xerox Star: A Retrospective Presented by: Liang Jin Weiwen Yang 1
Outline n n What is Star, Its Features and Design History of Star Development and Lessons From Experiences 2
Star: Feature & Design n n General Description of Star Machine and Network Level Window and File Manager Level User Interface Level Document Editor Level 3
General Description of Star n n n n Star was designed as an office automation system and It was introduced 1981. The idea was that professionals like to have work station on the desk and use them to produce , retrieve, distribute and organize documentation, presentations, memos and reports Workstations would be connected via Ethernet and share file servers and printers, … Star used a bitmapped screen, windows, a two-buttoned mouse and icons, it was new. Desktop metaphor Generic commands (Copy, move, delete…) Manipulate graphical elements on screen 4
Machine and Network Level n n Star was designed to operate in a distributed computing environment. It combines the advantage and avoids the disadvantage of two primary to interactive computing: Time sharing system and stand-alone personal computers 5
Machine and Network Level (continue) n n Mouse: provide a way for users to indicate which operations they want and what data they want those operations to be performed on. Two button mouse in Star. One button in Apple. Predecessors of Star used three button mouse Why did Star use two button mouse ? Bitmapped Display 6
n View. Point Screen Image, Bitmapped Display 7
Window and File Manager Level n Windows n n allow several programs to display information simultaneously in separate areas of the screen Integrated Applications n User doesn’t need to specify certain application to open and edit documents including text, graphs, spreadsheet, etc 8
User Interface Level n n n Desktop Metaphor: represent the physical objects. Deal mainly with data files. Tools Metaphor: deal mainly with application as tools Generic commands: a small set of generic commands. achieves simplicity without sacrificing functionality. 9
User Interface Level (continue) n n Direct manipulation: Object represent task objects or functions. manipulate the interface object through pointing device. Star used approach by seeing and pointing. They want users to feel that they manipulate the data directly rather than issuing command to the system 10
User Interface Level (continue) n n Icons and Icon File Management Represent data file with pictures of office objects Star allows users to organize files spatially rather than by distinctive naming. Files in Star can be put in folders or clumped on desktop. 11
User Interface Level (continue) n n Few Modes: A system has modes if user actions differ in effects or availability in different situations. Star avoids modes in three ways: n n n One is the extensive use of generic commands, which reduces the number of commands needed. Second way is by allowing application operate simultaneously Third way is by using a noun-verb command syntax 12
User Interface Level (continue) n Objects have properties : n n Allow objects of the same type to vary in appearance, layout, and behavior Progressive Disclosure n Dictates the detail be hidden from users until they ask or need to see it. 13
Progressive Disclosure- Star Property Sheet 14
User Interface level (Continue) n n Consistency Emphasize on good graphic and screen design n n The Illusion of manipulable objects Visual Order and User focus Revealed the structure Consistent and appropriate graphic vocabulary Match the medium 15
Visual Order and User Focus 16
Visual order and User Focus 17
Revealed Structure 18
Match the Medium 19
Document Editor Level n WYSIWYG document editor Star Document are displayed as they will print Extended character set for multilingual capability ( 16 bit) Star assumes primary use of the system is to create and maintain documents n n n 20
Mathematical Formula 21
History of Star development n n Star was conceived a product in 1975 and was released in 1981. Many of its ideas were dated back more than three decades. 22
How system influenced later system 23
Pre -Xerox n Memex n n Sketch Pad n n Ivan Sutherland build an interactive graphics system that allowed users to create graphical figures on a CRT display using a light pen in 1960 s NLS system n n Envision a personal, desktop computer for non numerical applications in 1945 (too advanced? ) CRT display, full screen and mouse is used in 1960 s The Reactive Engine n Interactive applications don’t treat the screen as “ glass teletype” and can share the screen with other programs. 24
Xerox PARC n n PARC was established in 1970. It is for developing the Xerox existing product line, and Xerox planed expansion into the office system business n Topic: material science, laser physics, integrated circuitry, CAD, UI, CS 25
PARC Research n n n Alto: a minicomputer system, with 2. 5 MB hard disk, 128 to 256 kb memory in 1972 Ethernet: connected computers into a network, flexible Smalltalk: the prototype of portable machine developed by Alan Kay’s group evolved into Smalltalk language and programming environment. 26
PARC Research (Continue) n Pygmalion n n Bravo, Gypsy and Bravo. X n n Direct descendent of Bravo. X Lisa. Write n n Advanced document editing system for Alto Microsoft Word n n First large program written in Smalltalk. Programming a computer does not have to be primary in a textual activity. a descendent of Bravo. X, for Apple Draw n Graphical object editors that allowed users to construct figures out of selectable, movable, stretchable geometric forms and text. 27
PARC Research (Continue) n Markup n n Laser Printing n n describe output to laser printer (Press) Laurel and Hardy n n a bitmap graphics editor Display-oriented tool for sending, receiving, and organizing e-mail. Office. Talk n supported standard office automation tasks and tracked "jobs" as they went from person to person in an organization 28
Star n Star Hardware n n n 8000 series workstation 384 kb Memory, 10, 29, 40 MB Disk, 17 inch Display, mechanical mouse, 8 -inch floppy, ethernet Star Software n n Incorporated ideas from predecessors, as well as new ideas, and produced coherent design most of the design and prototyping work was done in Palo Alto, whereas most of the implementation was done in El Segundo. 29
Tajo/XDE n n Early prototyping and development was done on Altos and successor research machines The development environment, known internally as Tajo and externally as Xerox Development Environment (XDE), 30
View Point n View. Point Software n n n View. Point Hardware n n n Rewrite Star according to the Tajo model Involve user control 6085 workstation 1 MB Memory, 10 -18 MB Disk, 15 or 19 -inch display, optical mouse, 5. 25 -inch floppy, ethernet. Recent Viewpoint Changes n n Xerox Pro. Illustrator Shared Books Redlining Feature Cursor Keys 31
Lessons from Experience n n n Pay attention to industry trends problem. Pay attention to what customers want. Know your competition Avoid geographically-split development organizations Don't be dogmatic about the Desktop metaphor and Direct Manipulation Many aspects of Star were correct 32
Many aspects of Star were correct n n n n Iconic, direct-manipulation, object-oriented user interface Generic commands and consistency in general Pointing device High-resolution display Good graphic design 16 -bit character set Distributed, personal computing 33
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