Anyone with an interest in AI will know of Alan Turing - he, along with a handful of other mathematical geniuses with a penchant for the pragmatic, lay down the foundations of modern computer science.
Turing is known primarily for the contributions that bear his name - that is, Turing machines, and the Turing test (although just what the Turing test is supposed to be testing, and whether it can actually discern what it's supposed to be testing for, is an issue that has never quite been resolved to anyone's satisfaction).
These two ideas were laid out in two supremely famous papers - the Turing test is described in Turing's, much read, paper Computing machinery and intelligence (although Turing called it the "imitation game"), and his Turing machine is described in the much less widely read (there are far clearer and accessible treatments than his original paper - but I don't think that's why people don't read it) On Computable Numbers, with an Application to the Entscheidungsproblem
However, there is a third paper that deserves to be equally well known - that is his remarkable paper "Intelligent machinery" (not to be confused with the similarly named "Intelligent Machinery, a heretical theory" - I would guess that it is generally unknown because Turing never actually published it which is a real shame. In B. Jack Copeland's words the paper
is a wide-ranging and strikingly original survey of the prospects for Artificial Intelligence. In it Turing brilliantly introduced many of the concepts that were later to become central in the field (Copeland 2004 : 401)
These concepts included brief treatments of genetic algorithms, logic based programming, and an early description of the Turing test - however
"[t]he major part ... consists of an exquisite discussion of machine learning, in which Turing anticipated the modern approach to AI known as connectionism" (Copeland 2004 : 401)
If you're at all interested in the history of AI, Turing, or the ideas that have shaped our last century - you can (and should) read this document, available in Copeland's collection The essential Turing
Copeland, B. J. (ed) 2004. The essential Turing. Oxford : Oxford University Press