C is a general-purpose, high-level programming language that was originally developed by Dennis Ritchie to develop the UNIX operating system. Some key facts about C include that it was first implemented in 1972 on DEC PDP-11 computers, it can be compiled on many platforms, and produces efficient programs while also allowing low-level activities. C was created to write the UNIX operating system and is widely used today for operating systems, language compilers, databases, and other systems programming needs due to its ability to generate fast code close to assembly language.