I recently learned that Dennis Ritchie (of “Kernighan and Ritchie” fame) passed away a few days ago. He will be very much missed by the technical community. How many people can say that they were the principal designer of (and co-wrote THE book on) C — the single most influential computer language ever written?
If you Google “C programming language,” the top result is the Wikipedia description of the language itself. Just under that is the Wikipedia article on the book of the same title. Those of us in the industry refer to it as “Kernighan and Ritchie,” “The Book,” “K&R,” “The Bible,” and “The Book of C.” It’s a small, unassuming book — but very well-written. It provides a solid yet approachable introduction to programming in C. (It’s also responsible for the “Hello, World!” programming meme, started in a Bell company memo by Ritchie’s co-author Brian Kernighan.) If I had to cut my library down to only the books I could fit in my backpack, my copy of K&R would be included, no question about it.
C is almost literally everywhere. Microcontrollers with firmware written in C run our cars, make our coffee, and guide us to our destinations. More powerful CPUs running programs written in C are used in our computers and smartphones. The Linux kernel is written largely in C, and Windows and Mac OS also no doubt contain at least significant amounts of C code. Android programs may be written in (C-based) Java, but the underlying OS is written in C. The computer I’m using to type these words is running a browser (Chrome) no doubt written in a C-like language. The webserver which hosts this site runs the “LAMP stack“: Linux (written in C); the Apache webserver (written in C); MySQL (written in C and C++); and PHP (written in C). The routers shepherding the packets containing this text use firmware that is almost certainly written in C.
Although C was written between 1969 and 1973 as an operating-system language, it is still very much in widespread use today, and has inspired and influenced many other languages. Programs written in C++, C#, Java, Perl, PHP, Go, and others all owe their basic syntax and structure to C.
C is still widely used after so many years because it manages to be most things to most people. It is a very fast, efficient compiled language (nearly as fast as hand-written assembly code, in most cases), yet is far easier to learn and use than assembly. It can be used to write complex, multithreaded operating systems, create virtual 3D game worlds, or to write simple programs to make 40-cent microcontrollers blink an LED or run a toaster.
RIP, Mr. Ritchie. Thanks for giving the world one of the solid cornerstones of the Information Age.
