Contribution
Joined Bell Labs in 1967, Aho co-authored a number of research papers, first with Jeff Ullman, and then with several other co-workers. He soon stumbled upon what would become the UNIX project, and found that using the early system "was a much nicer way to write papers than the old traditional way". Through UNIX, Aho helped develop automata theory and its applications to programming language parsing and compilation.
Fun Facts:
Aho is the "A" in the command AWK. This language was named by its authors, Al Aho, Peter Weinberger and Brian Kernighan.