Editing Spreadsheet (section)

=== VisiCalc for the Apple II===
[[File:Visicalc.png|thumb|VisiCalc running on an Apple II]]

The concept of spreadsheets became widely known due to [[VisiCalc]], developed for the [[Apple II]] in 1979 by VisiCorp staff [[Dan Bricklin]] and [[Bob Frankston]].
Significantly, it also turned the [[personal computer]] from a hobby for computer enthusiasts into a business tool.

VisiCalc was the first spreadsheet that combined many of the essential features of modern spreadsheet applications, such as a [[WYSIWYG]] interactive user interface, automatic recalculation, status and formula lines, range copying with relative and absolute references, and formula building by selecting referenced cells. Unaware of LANPAR at the time, ''[[PC World]]'' magazine called VisiCalc the first electronic spreadsheet.<ref>{{Cite web |url=http://www.pcworld.com/article/id,116166/article.html |title=PC World– Three Minutes: Godfathers of the Spreadsheet<!-- Bot generated title --> |access-date=2008-02-22 |archive-date=2008-07-26 |archive-url=https://web.archive.org/web/20080726090701/http://www.pcworld.com/article/id,116166/article.html |url-status=dead }}</ref>

Bricklin has spoken of watching his university professor create a table of calculation results on a [[blackboard]]. When the professor found an error, he had to tediously erase and rewrite several sequential entries in the table, triggering Bricklin to think that he could replicate the process on a computer, using the blackboard as the model to view results of underlying formulas. His idea became VisiCalc.

VisiCalc for the [[Apple II]] went on to become the first [[killer application]],<ref>Power, D.J., ''[http://www.dssresources.com/history/sshistory.html A Brief History of Spreadsheets] {{Webarchive|url=https://web.archive.org/web/20210506205125/http://www.dssresources.com/history/sshistory.html |date=2021-05-06 }}'', DSSResources.COM, v3.6, 8 August 2004</ref><ref name="cacASU">"Killer Applications" (overview), Partha gawaargupta. [[Arizona State University]] in Tempe, Arizona, May 2002, Web page: [http://cactus.eas.asu.edu/partha/Columns/2002/07-01-killer-app.htm ASU-killer-app] {{Webarchive|url=https://web.archive.org/web/20110929024420/http://cactus.eas.asu.edu/partha/Columns/2002/07-01-killer-app.htm |date=2011-09-29 }}.</ref> a program so compelling, people would buy a particular computer just to use it. It was [[ported]] to other computers, including [[CP/M]] machines, [[Atari 8-bit computers]], and the [[Commodore PET]], but VisiCalc remains best known as an Apple II program.