For those who don’t know, Dennis Ritchie was one of the creators of UNIX and the man who designed the C programming language. The contributions those two things made to the computer science field is incalculable. If you’re sitting at a machine running OS X you’re running UNIX and regardless of what you’re running chances are at least parts of it were written in C.
The legacy of UNIX and C can only be described as astronomical. UNIX’s design philosophy can be found in everything ranging from the various flavors of BSD to Linux and all of them are written in C. It’s rare for a technology to last more than a few scant years but both of Ritchie’s well-known contributions are not only used to this day but they’re pervasive. I would argue that this man’s contribution to the computer field surpasses that of Steve Jobs but being Ritchie’s contributions were all behind the scenes they remain less known.
So long Dennis Ritchie, you’ll be missed. Your contributions to the field of computer science quite literally changed the world for the better.