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The Xerox Star: A Retrospective. Part 1 By: Frank Lin. What is Star?. Star was introduced as the 8010 “Star” Information System in April of 1981
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The Xerox Star: A Retrospective Part 1 By: Frank Lin
What is Star? • Star was introduced as the 8010 “Star” Information System in April of 1981 • It was designed as an office automation system where workers would produce, retrieve, distribute, and organize documentation, presentations, memos, and reports
Star Assumptions • Workers just interested in getting their work done and not interested in computers • Star’s users are casual, occasional users
Hence… • The system was made to be “invisible” to the user • Also, the goal was to make Star easy to learn and remember
Distributed PC • Star designed to operated in a distributed computing environment • Combined the advantages but avoided the disadvantages of time-shared systems and stand-alone personal computers • Star is connected by a local area network with shared resources
Mouse • Very important device for Star • Allowed the user to use easily navigate on the video display • Star employed a two-button mouse instead of the one-button and three-button mouse
Display • Star used a bitmapped display instead of a character display • This allowed for better navigation on the system with a mouse
Window and File Manager • Windows were used to display multiple information simultaneously • Windows could be overlapped or not overlapped • The latter choice was chosen because it was shown that users spend a lot of time adjusting the windows so they wouldn’t overlap
Star • Star also tried to integrate the different types of documents • Star was not fully integrated in that the different documents could not be edited by any program
Star’s User Interface • 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 • Star resembles an office desk with surrounding furniture • The user is unaware of the programs within the system • The user believes that they are manipulating objects within an office
Generic Commands • Simple commands that can be used from program to program • They are defined consistently from program to program • Does not use unnecessary modifiers
Direct Manipulation and Graphical User Interface • Users manipulated objects on the screen • They are not entirely menu driven • Allowed users to learn and retain easier
Icons and Iconic Management • Files are represented by icons with pictures • Each type of file has a characteristic icon representation • Allows for users to organize spatially rather than according to distinctive naming
Few Modes • A system has modes if user actions differ in effects or availability in different situations • It was believed modes should be avoided as much as possible • Extensive use of generic commands and allowing applications to operate simultaneously reduced modes
Objects have Properties • Objects of the same type can vary according to different properties • Properties are changed in Star through graphical forms called property sheets • These types of systems are rare
Progressive Disclosure • Principle that details are hidden from the user until the user ask or needs to see it • Star provides default settings and hides settings • It is used in property sheets
Emphasis on Good Graphic and Screen Design • The illusion of manipulability objects • Visual order and user focus • Revealed structure • Consistent and appropriate graphic vocabulary • Match the medium • WYSIWYG document editor • Extended character set for multilingual capability • Document is the heart of the system
History of Star Development Part 2 By: Richard Huynh
Pre-Xerox • Although Star was conceived as a product in 1975 and was released in 1981, many of the ideas that went into it were born in projects dating back more than three decades. • Memex (1945) • Sketchpad (1960’s) • Smalltalk (1960’s)
Pre-Xerox (cont.) • Memex (1945) • Vannevar Bush, one of President Franklin D. Roosevelt’s science advisor, envisioned a personal computer and wrote an article describing his vision of the uses of electronics and information technology. But due to insufficient technology and insufficient imagination of others, his ideas languished for 15 years.
Pre-Xerox (cont.) • Sketchpad (1960’s) • Ivan Sutherland (now with Sun Microsystems) built an interactive graphics system called Sketchpad that allowed a user to create graphical figures on a CRT display using a light pen. Sketchpad influenced Star’s user interface as a whole as well as its graphics applications.
Pre-Xerox (cont.) • Smalltalk (1960’s) • Alan Kay, then a graduate student, wrote a dissertation, The Reactive Engine, which contained the seeds of many ideas that he and others later brought to development in the Smalltalk language and programming environment, which influenced Star.
Xerox PARC • In 1970, Xerox established a research center in Palo Alto. The Palo Alto Research Center (PARC), was organized into several laboratories.
Xerox PARC (cont.) • Among the founding members of PARC was Alan Kay. • He and his colleagues were dedicated to a vision of personal computers in a distributed environment. In fact, they coined the term “personal computer” in 1973.
Xerox PARC (cont.) • One result of the search for a personal-like computer was the Alto. • The first Alto became operational in 1972.
Xerox PARC (cont.) • Another product of the new approach was the Ethernet. • Ethernet provided a way of connecting computers much more flexibly than previously possible. Soon after the first Altos were built, they were networked together. • The Ethernet, with its standard communication protocols, became a networking standard.
Pygmalion • The first large program to be written in Smalltalk was Pygmalion. • One goal of Pygmalion was to show that programming can be accomplished by interacting with graphical elements on a screen.
Pygmalion (cont.) • A second goal was to show that 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. • The idea of using icons came mainly from Pygmalion.
Other software's for Alto • Bravo • Gypsy • BravoX • Microsoft Word • Markup • Laser Printing • OfficeTalk
Star • To develop Star, Xerox created the Systems Development Department. • SDD was split between two locations: El Segundo (SoCal) and Palo Alto (NoCal). • 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.
Star (Xerox 8010) • The official name for Star was the “Xerox 8010,” Star was only an internal name.
Major Problem with Star • 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 also did not lend itself to distributed, multiparty development. • Star’s infrastructure was rewritten according to the Tajo model.
Lessons Learned • 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. • 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 Learned (cont.) • Know your competition. • 1981 – $16,595 per workstation. • Avoid geographically split development organizations. • Organization split between Palo Alto and El Segundo was probably a mistake.
