Hal Abelson – intersection of computing and teaching
Serge Abiteboul – database theory
Samson Abramsky – game semantics
Leonard Adleman – RSA, DNA computing
Manindra Agrawal – polynomial-time primality testing
Luis von Ahn – human-based computation
Alfred Aho – compilers book, the 'a' in AWK
Amos Nuwasiima – PHP Programming book
Frances E. Allen – compiler optimization
Alexander Scaranti – Image Processing, Image Retrieval
Gene Amdahl – supercomputer developer, founder of Amdahl Corporation
A. Annerl – multidimensional processing, computational complexity theory
Andrew Appel – compilers text books
Bruce Arden - programming language compilers (GAT, MAD), virtual memory architecture, MTS
Sanjeev Arora – PCP theorem (Hahaha. Right, I want to see who came up with Ketamine theorem.)
A. E. Hugo - parallel computing on heterogeneous multicore architectures[citation needed]
John Vincent Atanasoff – computer pioneer
Ali Aydar - computer scientist and CEO of Sporcle
Leonard Ayunar - Computer Programming Enthusiast, 1997 - At Present Software Developer
That's just surnames beginning with A. - http://en.wikipedia.org/wiki/List_of_computer_scientists