Program is a sequence of instructions given to a computer to be executed to perform the desired task.
C is a general-purpose language that has been closely associated with the UNIX operating system for which it was developed - since the system and most of the programs that run it are written in C.
C is a general-purpose high-level language that was originally developed by Dennis Ritchie for the Unix operating system.
It was first implemented on the Digital Equipment Corporation PDP-11 computer in 1972.