Inventor of SmallTalk ...
Kay eventually got to work on the "Algo" printouts on his desk, and was thoroughly confused, there were many constructs he had never seen before and "the documentation read like Norwegian translated into English."[Kay93] What Kay had inadvertently been given was a copy of Simula-I. Looking over the printouts, and reading the documentation, he realized the immense potential of programming with constructs like Simula's activities and processes, or Sketchpad's masters and instances. Kay quickly developed a vague idea for programming by not only breaking the problem down into smaller sub problems, but by breaking the computer down into thousands of smaller simulated computers (or objects) to solve all of the sub problems.
Kay began working on "personal computers" with an eye towards an "object oriented" interface. In 1970 left Utah to work for Xerox PARC, and began developing a desktop computer or use by children called "KiddiKomp" (later "miniCOM") which had a combination programming language / user interface called Smalltalk(-71) to stress it's ease of use.
Smalltalk was redefined from scratch in 1972 on a bet, (that Kay could define the
most powerful language in the world* ina page of code) and Smalltalk-72 has since been considered the first "real Smalltalk". Smalltalk was redesigned again in 1976 by Dan Ingalls, and then again in 1980 just before it was released to the public. *
See also :
StewartBrand writing about AlanKay (and SpaceWar) in 1972! : http://www.wheels.org/spacewar/stone/rolling_stone.html