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AtariWiki V3: VisiCalc
src: atariwiki.org

VisiCalc (for "visible calculator") was the first spreadsheet computer program for personal computers, originally released for the Apple II by VisiCorp. It is often considered the application that turned the microcomputer from a hobby for computer enthusiasts into a serious business tool, prompting IBM to introduce the IBM PC two years later. VisiCalc is considered the Apple II's killer app. It sold over 700,000 copies in six years, and as many as 1 million copies over its history.

Initially developed in a 6502 assembler running on the Multics time sharing system, VisiCalc was ported to numerous platforms, both 8-bit and some of the early 16-bit systems. In order to do this, the company developed porting platforms that produced bug compatible versions. The company took the same approach when the IBM PC was launched, producing a product that was essentially identical to the original 8-bit Apple II version. Sales were initially brisk, with about 300,000 copies sold.

VisiCalc used the A1 notation in formulas.

When Lotus 1-2-3 was launched in 1983, taking full advantage of the expanded memory and screen of the PC, VisiCalc sales practically ended overnight. Sales imploded so rapidly that the company was soon insolvent. Lotus Development purchased the company in 1985, and immediately ended sales of VisiCalc and the company's other products.


Video VisiCalc



History

VISICALC represented a new idea of a way to use a computer and a new way of thinking about the world. Where conventional programming was thought of as a sequence of steps, this new thing was no longer sequential in effect: When you made a change in one place, all other things changed instantly and automatically.

-- Ted Nelson

VisiCalc was created after Dan Bricklin watched a presentation while attending Harvard Business School. The professor was creating a financial model on a blackboard that was ruled with lines to create a table, and formulas and data were being written into the cells. When the professor found an error or wanted to change a parameter, he had to erase and rewrite a number of sequential entries in the table. Bricklin realized that he could replicate the process on a computer using an "electronic spreadsheet" to view results of underlying formulae.

Bricklin was joined by Bob Frankston, and the pair worked on VisiCalc for two months during the winter of 1978-79, forming Software Arts. Bricklin wrote that

with the years of experience we had at the time we created VisiCalc, we were familiar with many row/column financial programs. In fact, Bob had worked since the 1960s at Interactive Data Corporation, a major timesharing utility that was used for some of them and I was exposed to some at Harvard Business School in one of the classes.

Bricklin was referring to the variety of report generators that were in use at that time, including Business Planning Language (BPL) from International Timesharing Corporation (ITS) and Foresight, from Foresight Systems. However, these earlier timesharing programs were not completely interactive, nor did they run on personal computers.

Frankston described VisiCalc as a "magic sheet of paper that can perform calculations and recalculations", which "allows the user to just solve the problem using familiar tools and concepts". Personal Software began selling it in mid-1979 for under $100, after a demonstration at the fourth West Coast Computer Faire and an official launch on June 4 at the National Computer Conference. It required an Apple II with 32K of random-access memory (RAM), and supported saving files to magnetic tape cassette or Apple's Disk II floppy disk system.

VisiCalc was unusually easy to use and came with excellent documentation; Apple's developer documentation cited the software as an example of one with a simple user interface. Observers immediately noticed its power. Ben Rosen speculated in July 1979 that "VisiCalc could someday become the software tail that wags (and sells) the personal computer dog". For the first 12 months it was only available for the Apple II, and became that platform's killer app. Many bought $2000 Apples to run the $100 software--more than 25% of those sold in 1979 were reportedly for VisiCalc--even if they already owned computers. Apple's rival Tandy Corporation used VisiCalc on its own Apple IIs. Other software supported its Data Interchange Format (DIF) to share data. One example was the Microsoft BASIC interpreter supplied with most microcomputers that ran Visicalc. This allowed skilled BASIC programmers to add features such as trigonometric functions that Visicalc itself did not have.

Bricklin and Frankston's original intention was to fit the program into 16k, but this proved impossible and 32k became necessary. Some additional features they wanted like a split text/graphics screen still had to be omitted for space reasons. However, Apple eventually began shipping all Apple IIs with 48k following a drop in RAM prices and so this was no longer an issue. The initial release supported cassette storage, but that was quickly dropped.

At its release Personal Software promised ports to other computers, starting with those using the 6502 CPU, and versions appeared for the Atari 800 and Commodore PET, both of which could be done easily because those computers used the same processor as the Apple II, and large portions of code could be reused. The PET version, which contained two separate executables for 40 and 80-column models, was widely criticized for having a very small amount of worksheet space due to the developers' inclusion of their own custom DOS which used a large amount of memory (the PET only had 32k versus the Apple II's available 48k).

Other ports followed for the Apple III, Zilog Z-80-based Tandy TRS-80 Model I, Model II, Model III, Model 4, and Sony SMC-70. The TRS-80 Model I and Sony SMC-70 ports were the only versions of VisiCalc without copy protection. The Sony SMC-70 was the only CP/M version. Most versions were disk-based, but the PET VisiCalc came with a ROM chip that the user had to install in one of the motherboard's expansion ROM sockets. The most important port was for the IBM PC, and VisiCalc was one of the first commercial packages available when the IBM PC shipped in 1981. It quickly became a best-seller on this platform, in spite of being severely limited to be compatible with the versions from the 8-bit platforms. It is estimated that 300,000 copies were sold on the PC, bringing total sales to about 1 million copies.

By 1982 VisiCalc's price had risen from $100 to $250. Several competitors appeared in the market, notably SuperCalc and Multiplan, each of which added more features and corrected deficiencies in VisiCalc, but could not overcome its market dominance. A more dramatic change occurred with the 1983 launch of Lotus Development Corporation's Lotus 1-2-3, written by a former VisiCalc employee. Unlike the PC version of VisiCalc, 1-2-3 was written to take full advantage of the PC's increased memory, screen and performance. Yet it was designed to be as compatible as possible with VisiCalc, including the menu structure, to allow VisiCalc users to easily migrate to 1-2-3.

1-2-3 was almost immediately successful, and by 1984 InfoWorld wrote that sales of VisiCalc were "rapidly declining", stating that it was "the first successful software product to have gone through a complete life cycle, from conception in 1978 to introduction in 1979 to peak success in 1982 to decline in 1983 to a probable death, according to industry insiders, in 1984." The magazine added that the company was slow to upgrade the software, only releasing an Advanced Version of VisiCalc for the Apple II in 1983 and announcing one for the IBM PC in 1984. By 1985 VisiCorp was insolvent. Lotus Development acquired Software Arts and ended sales of the application.

Releases

  • 1979: Apple II
  • 1980: Apple III, TRS-80 Model III, Apple II, IBM PC, TRS-80 Model 2, Commodore PET CBM-80, HP 125, Atari 800
  • 1981: IBM PC, Sony SMC-70
  • 1982: Apple III, Apple IIe--VisiCalc Advanced Version
  • 1983: TRS-80 Model 4 Enhanced Visicalc (could use 64 KB banked memory in an expanded machine)

Maps VisiCalc



Reception

In 1983 Softline readers named VisiCalc tenth overall, and the highest non-game, on the magazine's Top Thirty list of Atari 8-bit programs by popularity. II Computing listed it second on the magazine's list of top Apple II software as of late 1985, based on sales and market-share data.

In its 1980 review, BYTE wrote "The most exciting and influential piece of software that has been written for any microcomputer application is VisiCalc". It concluded, "VisiCalc is the first program available on a microcomputer that has been responsible for sales of entire systems". Creative Computing's review the same year similarly concluded, "for almost anyone in business, education, or any science-related field it is ... reason enough to purchase a small computer system in the first place". Compute! reported, "Every Visicalc user knows of someone who purchased an Apple just to be able to use Visicalc". Antic wrote in 1984, "VisiCalc isn't as easy to use as prepackaged home accounting programs, because you're required to design both the layout and the formulas used by the program. Because it is not pre-packaged, however, it's infinitely more powerful and flexible than such programs. You can use VisiCalc to balance your checkbook, keep track of credit card purchases, calculate your net worth, do your taxes--the possibilities are practically limitless." The Addison-Wesley Book of Atari Software 1984 gave the application an overall A+ rating, praising its documentation and calling it "indispensable ... a straight 'A' classic".

In 2006, Charles Babcock of InformationWeek wrote that, in retrospect, "VisiCalc was flawed and clunky, and couldn't do many things users wanted it to do."


Before Excel there was VisiCalc: An interview with its creators ...
src: i.ytimg.com


See also

  • Visi On
  • Triumph of the Nerds, A documentary hosted by Robert X. Cringely that featured the creators of VisiCalc and their contribution as the first killer app for the personal computer.
  • Timeline of computing 1950-1979

AtariWiki V3: VisiCalc
src: atariwiki.org


References


AtariWiki V3: VisiCalc
src: atariwiki.org


Further reading

  • Grad, B. (2007). "The Creation and the Demise of VisiCalc". IEEE Annals of the History of Computing. 29 (3): 20-20. doi:10.1109/MAHC.2007.4338439. 
  • Campbell-Kelly, M. (2007). "Number Crunching without Programming: The Evolution of Spreadsheet Usability". IEEE Annals of the History of Computing. 29 (3): 6-8. doi:10.1109/MAHC.2007.4338438. 

Visicalc - YouTube
src: i.ytimg.com


External links

  • Dan Bricklin's Own VisiCalc Website - With history information as well as downloadable PC version
  • Implementing VisiCalc - By Bob Frankston, on his website
  • Was VisiCalc the "first" spreadsheet? - By Dan Bricklin, on his website
  • Three Minutes: Godfathers Of The Spreadsheet - PC World  interview with the creators of VisiCalc
  • Techdirt: What If VisiCalc Had Been Patented?
  • TRS-80 and more
  • TED Talk - "Dan Bricklin: Meet the inventor of the electronic spreadsheet"
  • TEDx Talk - "A Problem That Changed The World | Dan Bricklin | TEDxBeaconStreet"

Source of the article : Wikipedia

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