The first computer spreadsheet program developed by DanBricklin and BobFrankston. The archetypal KillerApp, it was responsible for a lot of AppleIi sales. Apple arguably wouldn't be around today without this early boost because they couldn't fund the Mac and GUI projects without the revenue. The reasons it was developed for the Apple first tend to vary. One story is that the Commodore Pet and TRS-80 were taken by other projects. Another is that Steve Jobs gave them some Apple computers in exchange for porting another product of the company over to Apples.
See http://www.bricklin.com/history/sai.htm for DanBricklin's history of SoftwareArts? and VisiCalc.
So, what features did it have, and what did it lack that we take for granted today?
VisiCalc on the internet
Everything you want to know can be found at the above website, including an executable of VisiCalc itself, which, miraculously, still runs. http://www.bricklin.com/history/vcexecutable.htm for the download. (I've run it under Windows XP.) It is a whopping 27.5KB. That's kilobytes.
Among things it did not have was an underlying window system, ability to product charts, any embedded programming language, and provision for using a mouse (there were no commercial mice at that time).
-- DanWeinreb
An emulation of the paper spreadsheet
Most software is more or less an adaptation of a non-software system (word processor; typewriter; database: column systems; accounting software: accounting books etc.
VisiCalc was a software emulation of the physical, paper spreadsheet that had been used by accountants for ages. The idea was that the number in one cell may come from a formula. Of course, the cells contained values only - the innovation was in making cells able to contain automated computations
As a young, naïve engineer whose first OS was Windows 98, VisiCalc for me came across as a spreadsheet version of ViEditor: commands are a slash and 1-3 keystrokes. -- DaNuke?