Winners of the A.M.Turing Award, the Nobel Prize of computing, describe their singular contributions to the field, and their works’ impact. They also find time to discuss the current and future state of computer science. Moderator Stephen Ward starts with 1990 prize winner Fernando Corbato, who remembers MIT’s 100th birthday celebration. Corbato pioneered the idea of timesharing, and notes “how frozen the attitude of industrialists and computer manufacturers were.” They resisted the idea of timesharing, not understanding “why they needed to change anything.” The ultimate goal of his work, says Corbato, was “man-machine interaction.” His achievements led to Unix and C programming language and “are being rediscovered today in cloud computing.” 1992 award winner Butler Lampson describes the nearly free rein Xerox gave him and colleagues at PARC starting in 1970, which led to the first personal computer, a series of LISP machines, and other revolutionary technologies that developed into “pretty much all the things you’re now accustomed to in the world of personal computing,” he says. The only vision Lampson was unable to explore was the web, and that was “because we didn’t have a big enough sandbox to play in.” Andrew Chi-Chih Yao earned his 2000 Turing for the complexity-based theory of pseudorandom number generation, cryptography and communication complexity. Yao attributes his successes in part to the times (late ‘70s), when it became apparent that public key cryptography would herald big networks, electronic commerce and the need for cryptography. He also notes that a group of researchers were “trying to break away from Claude Shannon” and “embraced computational complexity as our savior.” It should come as no surprise, given these trends, says Yao, “those of us lucky enough in those days to be thinking about these issues would come up with concepts that would become very important.” Inspired by a paper in public key cryptography, Ronald Rivest and MIT colleagu...