VisiCalc, short for “Visible Calculator,” was the first spreadsheet program and the first fully functional computer application to run on personal computers. The program was created for the Apple II computer in 1979 by Harvard Business graduate student Dan Bricklin and his partner, Bob Frankston. VisiCalc was critical in demonstrating that personal computers could be a useful tool for small businesses. VisiCalc remains known as the "killer” application for Apple II because it made people want to go out and buy the Apple II computer.
Prior to the VisiCalc invention, computers could only run a few games and BASIC, a computer programming language. Originally called Calculedger, the VisiCalc spreadsheet software was a cross between a calculator and ledger, capable of calculating financial projections and complex “what if” scenarios, using mathematical relationships between numbers. The idea came to Bricklin in the spring of 1978 while daydreaming in classes. He and Frankston set to work on the program, building it over a weekend on a borrowed Apple II computer from friend, Dan Fylstra, whose software company they would partner with to market their new product.
VisiCalc was a fourth generation software program that ran on a 32-byte Apple II computer. It contained all the features typically found in modern spreadsheet software, and also included a graphical user interface incorporating “what you see is what you get,” or WYSIWYG, design. It used a slash-based menu system, @ functions, and was limited in size to 63 columns and 254 rows.
The software could format numbers as integers, decimals, scientific notation or graphs, and contained built-in numeric-only functions called SUM, MAX, AVERAGE, and LOOKUP, as well as common trigonometric and logarithmic functions. Additional features included status and formula labeling and range copying with absolute or relative references.
Bricklin's spreadsheet application debuted at the West Coast Computer Fair in San Francisco on May 1979, generating considerable buzz. Computer VisiCalc was offered for public sale five months later in October. Initially priced at $100 US Dollars, it landed atop the bestseller lists and sold more than 12,000 copies each month. Bricklin and Frankston eventually went on to adapt their spreadsheet application for the Tandy TRS-80, Commodore PET and Atari 800 platforms.
VisiCalc was eventually supplanted by more powerful versions, such as SuperCalc in 1980 and Microsoft Excel in 1983. The original software, which was never patented by its creators, was bought by Lotus Development Corporation and used as the basis for their own popular spreadsheet product, Lotus 1-2-3. Today, Dan Bricklin continues to maintain a modified, but working, copy of the program on his website. It is available for free as a free 27 kilobyte download.