A post to note the passing on of Dennis Ritchie (1941-2011), co-developer of C programming language and of the Unix operating system.  The Guardian’s obituary is here, a brief note from Wired Magazine here, and John Naughton’s tribute in the Observer here.    So much of modern technology we owe to just a few people, and Ritchie was one of them.
An index to posts about the Matherati is here.