1979– Visicalc is released by Dan Bricklin. The spreadsheet application is called the first killer app for personal computers. It turned the PC from a hobby to a business tool. Only downfall for Bricklin was he did not patent the system, therefore, clones like SuperCalc, Microsoft’s MultiPlan and Lotus 1-2-3, would show up. This Day in Tech History podcast show notes for October 11 IBM 1311 Storage Drive Office 2001 for Mac Poloroid files Chapter 11