Algorithm animation
1966 Knowlton, Bell Labs, Animation of linked-list language
1981 "Sorting our Sorting" Baecker, U. Toronto
1984 Balsa, M. Brown, Brown U., full-fledged algorithm animation system
1988 UW Illustrating Compiler R. Henry, UW, automatic insertion of animation code during compilation
1990 Tango, John Stasko, Brown U., full-fledged algorithm animation system
1991 Zeus (successor to Balsa)
1993 Polka, J. Stasko, Georgia Tech (extension of Tango to parallel computation)