Xerox Star
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The Star workstation, officially known as the 8010 Star Information System, was introduced by Xerox Corporation in 1981. It was the first commercial system to incorporate various technologies that today have become commonplace in personal computers, including a bitmapped display, a window-based graphical user interface, icons, folders, mouse, Ethernet networking, file servers, print servers and e-mail.
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[edit] Background
The Xerox Palo Alto Research Center (PARC), was founded by Xerox Corporation in 1970 to serve as an internal think tank to develop new technologies in the hope of producing marketable products.
[edit] The Alto
Various individuals or groups within PARC independently pursued different digital technologies. The culmination of this development was the Alto, a workstation developed for internal use at Xerox and also distributed on a limited basis to a few universities. The Alto had many advanced features including a bitmapped display, icons, a mouse used as a pointer and Ethernet networking.
As a commercial product, the Alto was lacking. Every program had its own interface and operating it required technical knowledge. The system was not considered to be user-friendly enough for less sophisticated users in an office environment. The most common programs were the Bravo word processor; Laurel, an e-mail program and its successor Hardy; Sil, a vector drawing program; and Markup, a bitmap editor (paint program). There was no spreadsheet or database software.
[edit] The Star
The Star was not developed by PARC. In 1977, under the direction of Don Massaro, the Systems Development Department (SDD) was established in El Segundo, California with some members culled from PARC in Palo Alto, California for "SDD North" – a team that eventually grew to more than 200 developers. They were tasked with designing a new system that incorporated the best features of the Alto, was easy to use and could automate many office tasks. The initiative was dubbed "The Office of the Future" and its development was headed by David Liddle.
The competitive landscape of the era was dominated by costly mainframes and minicomputers equipped with dumb terminals that time-shared processing time of the central computer. On the other side of the spectrum, personal computers were simplistic, with limited processing power and the inability to communicate with other systems. Xerox saw a niche somewhere in between with a distributed processing architecture – smart workstations with centralized file and peripheral sharing.
[edit] User Interface
A good part of a year was taken up by meetings and planning, the result of which was an extensive and detailed functional specification (the Red Book). This became the bible for all development tasks. It defined the interface and enforced consistency in all modules and tasks. All changes to the functional specification had to be approved by a review team which rigorously maintained standards.
The key philosophy of the user interface was to mimic the office paradigm as much as possible in order to make it intuitive for users. The concept of WYSIWYG was considered paramount. Text would be displayed as black on a white background just like paper and the printer would replicate the screen using Interpress, a page description language developed at PARC.
The user would see a desktop that contained documents and folders, with different icons representing different types of documents. Clicking any icon would open a window. Users would not use programs (e.g. a text editor, graphics program or spreadsheet software), they would simply open the file and the appropriate application would appear.
The Star user interface was based on the concept of objects. For example in a word processing document, there would be page objects, paragraph objects, sentence objects, word objects and character objects. Once a user clicked on an object, they could invoke a standard function from special keys on the keyboard, such as Open, Delete, Copy and Move. There was also a "Show Properties" key used to display settings, called property sheets, for the particular object (e.g. font size for a character object). This greatly simplified the menu structure all the programs.
Object integration was designed into the system from the start. For example a chart object created in the graphing module could be inserted into any type of document. This type of capability did not become available in Microsoft Windows until OLE (Object linking and embedding) was introduced in Windows nine years later in 1990.
[edit] The Development Process
One Palo Alto group worked on the underlying operating system interface to the hardware and programming tools; teams in El Segundo and Palo Alto collaborated on development of the user interface and user applications.
The staff relied heavily on the very technologies that they were working on -- file sharing, print servers and e-mail. They were even connected to the Internet, known as the Arpanet at that time, which allowed them to communicate between El Segundo and Palo Alto.
The Star was implemented in the Mesa programming language, a direct precursor to Modula-2 and Modula-3. Mesa was not object-oriented, but tools and programming techniques were developed which allowed pseudo object-oriented design and programming. Mesa required programmers to create two files for every module, a definition module which specified data structures and procedures for each object and one or more implementation module that has the actual code for the procedures.
The Star team used a sophisticated integrated development environment known internally as Tajo and externally as Xerox Development Environment or XDE. Tajo had many similarities with the Smalltalk-80 environment, but it had many additional tools. For example, the DF version control system, which required programmers to check out modules before they could be changed. Any change in a module which would force dependent modules to change were closely tracked and documented. Changes to lower level modules required various levels of approval.
The software development process was intense. It involved a lot of prototyping and user testing. The software engineers had to develop new network protocols and data-encoding schemes when those used in PARC's research environment proved inadequate.
Initially, only Altos were available as development tools. These were not well suited to the extreme burdens placed by the software. Even the processor intended for the product proved inadequate and involved a last minute hardware redesign. Many software redesigns, rewrites, and late additions had to be made, some based on results from user testing, some based on marketing considerations, and some based on systems considerations.
A Japanese language version of the system was produced in conjunction with Fuji Xerox (code named "J-Star") as well as full support for international customers.
In the end, there were many features from the Star Functional Specification that had to be left at the table. The product had to get to market and the last several months before release focused on reliability and performance.
[edit] Hardware Description
Initially the Star software was developed on a hardware platform dubbed the Dolphin, however the complexity of the software eventually overwhelmed its limited configuration. At one point in Star's development, it would take more than one half hour to reboot the system.
The eventual Star workstation hardware was known as a Dandelion, or Dlion, based on the "Wildflower" architecture paper by Butler Lampson. Its microprogrammed, bit-sliced CPU ran a virtual machine for the Mesa programming language.
The system had 384KB memory (expandable to 1.5MB), a 10MB, 29MB or 40MB hard drive, an 8" floppy drive, mouse and an Ethernet connection. The 17" CRT display (black and white) was large by standards at the time. It was meant to be able to display two 8.5"x11" pages side by side in actual size.
[edit] Marketing of the Star
The Xerox Star was not originally meant to be a stand-alone computer, but was part of an integrated Xerox "personal office system" that also connected to other workstations and network services via Ethernet. Although a single unit sold for $16,000, a typical office would have to purchase at least 2 or 3 machines along with a file server and a print server. Dropping $50,000 to $100,000 for a complete installation was not an easy sell.
Later incarnations of the Star would allow users to purchase a single unit with a laser printer, but the Xerox Star is still considered by many to be a commercial failure because only about 25,000 units were sold.
Some have said that the Star was ahead of its time -- few outside of a small circle of developers really understood the potential of the system. Consider that IBM introduced the IBM PC powered by the comparatively primitive PC-DOS the same year that the Star was brought to market. Even Apple's Lisa, inspired by the Star and introduced 2 years later was a market failure, for many of the same reasons as the Star.
Another possible reason given for the lack of success of the Star lies with the corporate structure of Xerox itself. A longtime copier company, Xerox played to their strengths. They already had one significant failure under their belt in making their acquisition of Scientific Data Systems pay off. It is said that there were internal jealousies between the old line copier systems divisions that were responsible for bulk of Xerox's revenues and the new upstart division. Their marketing efforts were seen by some as half-hearted or unfocused. Furthermore, the most technically savvy sales representatives that might have sold office automation equipment were paid large commissions on leases of laser printer equipment costing up to a half-million dollars. No commission structure for 'decentralized' systems could compete.
Probably most significantly, Xerox strategic planners at the Xerox Systems Group (XSG) did not feel that they could compete against other workstation manufacturers such as Apollo Computers or Symbolics. The Xerox name alone was considered their greatest asset, but it did not produce customers.
Finally, by today's standards, the software would be considered very slow, taxing the limited hardware of the era. This was primarily due to a poorly implemented file system. Saving a large file could take minutes. Crashes could be followed by an hours long process called "scavenging". The diagnostic code '7511' would appear in the top left corner of the screen indicating a file scavenge. For some, this was too steep price to pay, even for such sophisticated software.
To give credit to Xerox, they did try many things in an attempt to jumpstart sales. The next release of Star was on a different more efficient hardware platform and involved significant rewriting to improve performance. The system was dubbed the Viewpoint 6085 and was released in 1985. The new hardware provided 1MB to 4MB of memory, a 10MB to 80MB hard disk, a 15" or 19" display, a 5.25" floppy drive, a mouse, Ethernet connector and a price of a little over $6,000.
Along with an attached laser printer, the Viewpoint could be sold as a standalone system. Also offered was a PC compatibility mode via an 8086 based expansion board. Users could transfer files between the Star system and PC based software. Even with a significantly reduced price, it was still a Rolls Royce in the world of inexpensive $2,000 personal computers.
In 1989, Viewpoint 2.0 introduced many new applications related to desktop publishing. Eventually, Xerox jettisoned the integrated hardware/software workstation offered by Viewpoint and offered the software only as GlobalView. This provided the Star interface and technology on an IBM PC compatible platform. The initial release required the installation of MESA CPU add-on board. The final release of GlobalView 2.1 ran as an emulator on top of Microsoft Windows 3.1, Windows 95 or Windows 98 and was released in 1996.
[edit] Legacy of the Star
Even though the Star product failed to make an impact in the marketplace, it laid important groundwork for the computers of today. Many of the ideas in Star, such as WYSIWYG, Ethernet, and network services such as Directory, Print, File, and internetwork routing have become commonplace in computers of today.
A trip to Xerox PARC by Apple Computer's Steve Jobs in 1979 led to the graphical user interface and mouse being integrated into the Apple's Lisa and, later, the first Macintosh.[1] Steve Jobs was shown the Smalltalk-80 programming environment, networking and most importantly the WYSIWYG, mouse-driven GUI interface provided by the Alto. Members of the Apple Lisa engineering team saw Star at its introduction at the National Computer Conference (NCC '81) and returned to Cupertino where they converted their desktop manager to an icon-based interface modeled on the Star.[2] The initial Macintosh interface was a simplified version of the Lisa interface (i.e., single-tasking), supporting only a single floppy drive instead of the hard drive of the Lisa (and Star).
The list of products that were inspired or influenced by the user interface of the Star include the Apple Lisa, the Apple Macintosh, GEM from Digital Research (the DR-DOS company), Microsoft Windows, Atari ST, Commodore Amiga, Elixir Desktop, Metaphor Computer Systems, Interleaf, Microsoft OS/2, OPEN LOOK (co-developed by Xerox), SunOS, KDE, Ventura Publisher and NeXTSTEP[3]. Adobe Systems PostScript was based on Interpress. Ethernet was further refined by 3Com, and has become the standard networking protocol.
Some people feel that Apple, Microsoft, and others plagiarized the GUI and other innovations from the Xerox Star, and believe that Xerox didn't properly protect its intellectual property. The truth is a bit more complicated. Many patent disclosures were in fact submitted for the innovations in the Star; however, at the time the 1975 Xerox Consent Decree, an FTC antitrust action, placed restrictions on what the company was able to patent.[4] In addition, when the Star disclosures were being prepared, the Xerox patent attorneys were busy with several other new technologies such as laser printing. Finally, patents on software, particularly those relating to user interfaces, were an untested legal area at that time.
Xerox did go to trial to protect the Star user interface. In 1988, Apple sued Microsoft for copyright infringement of its Macintosh user interface in Windows (Apple Computer, Inc. v. Microsoft Corp.). In 1990, Xerox filed a similar lawsuit against Apple; however, it was thrown out because a three year statute of limitations had already passed. (Apple eventually lost its lawsuit in 1994, losing all claims to the user interface.)[5]
[edit] References
- ^ PBS Triumph of the Nerds Television Program Transcripts: Part III. PBS (Public Broadcasting System). Retrieved on February 8, 2007.
- ^ An Interview with Wayne Rosing, Bruce Daniels, and Larry Tessler. Byte. Retrieved on February 8, 2007.
- ^ Xerox Star Research. John Redant. Retrieved on February 8, 2007.
- ^ The 1975 Xerox Consent Decree: Ancient Artifacts and Current Tensions. Willard K. Tom. Retrieved on February 8, 2007.
- ^ Copyright Apple vs. Microsoft Articles. New York Times. Retrieved on February 8, 2007.
[edit] External links
- The first GUIs - Chapter 2. History: A Brief History of User Interfaces
- Star graphics: An object-oriented implementation
- Traits: An approach to multiple-inheritance subclassing
- The design of Star's records processing: data processing for the noncomputer professional
- The Xerox "Star": A Retrospective.
- The Xerox "Star": A Retrospective. (with full-size screenshots)
- Dave Curbow's Xerox Star Historical Documents (at the Digibarn)
- The Digibarn's pages on the Xerox Star 8010 Information System
- Xerox Star 1981
- HCI Review of the Xerox Star
- GUI of Xerox Star
