What is the extension of program written in c language?
Most C programmers use a .c file name extension for executable C source code, and .h or no filename extension at all for source files containing definitions and interface specifications, so-called header files.Some C compilers inspect the file name extension and draw conclusions, but most will accept almost any filename convention.Other common filename extensions used in the C family of programming languages are .cpp and .hpp (C++) and .cs (C#). On operating systems with case-sensitive file names, these extensions are generally expected to be in lower case.