Inventor of the modern Electronic SpreadSheet.
An unacknowledged savior of Apple. At a time when Apple was losing market share, and with their sales in a slump, Dan Bricklin and (mostly coded by) BobFrankston (together, SoftwareArts?), brought forth a program that allowed a decidedly plastic modeling of numbers, interactively, on a computer monitor.
One of the direct effects of this was that people bought AppleComputers just to run VisiCalc. This program drove a sales recovery for Apple, but I don't ever recall having seen an acknowledgement from Apple to that effect.
VisiCalc was the second of the "big three" must-have applications that justified personal computing: 1) the WordProcessor [WordStar, MagicWand?, WordPerfect], 2) the SpreadSheet [VisiCalc, SuperCalc?, Lotus123] 3) the desktop DataBase [dBASE II, Paradox].
With those three things available to Joe Everyman, personal computing was from then on lodged firmly in the world of business.
CategoryPerson? (A category isn't consistently applied to such folk.)