.The first electronic spreadsheet. It was introduced at the West Coast Computer Faire in 1979 for the Apple II. Conceived by Dan Bricklin, a Harvard student, and programmed by a friend, Bob Frankston, it became a major success. It launched an industry and was almost entirely responsible for the Apple II being used in business. Thousands of $3,000 Apples were bought to run the $150 VisiCalc. VisiCalc was a command-driven program that was followed by SuperCalc, MultiPlan, Lotus 1-2-3 and a host of others, each improving the user interface. Spreadsheets have also been implemented on minis and mainframes. It all started with VisiCalc.

The original VisiCalc program that ran on the IBM PC in 1981 still runs on today's PCs.
You can download it to your PC and run it under Windows or DOS. It is only 27,520
bytes long (smaller than many GIFs and JPGs on the web).
Click on the link to go to the download page.
VisiCalc Executable for the IBM PC
VisiCorp also produced VisiOn in the early 80's the first Windows environment for PC's