What is C language?

Every Computer language is designed for some specific purpose. For example, Fortran was designed for scientific and mathematical calculations, COBOL (Common business Oriented Language) was designed for business applications. Similarly, C language was developed for programming in the operating system called UNIX. It was created by Dennis Richie in 1970’s. Actually, C was derived from a language called B which was written by Ken Thompson, hence the name C to indicate it is a successor of language B.

C is not a high-level language, instead, it is a mid-level language with the simplicity of high-level language and power of low-level language. As a result, programs written in C are very fast.

C is a small language with only 32 keywords (keywords are reserved words used by the language for doing specific tasks).

Features of C language

C is a compiled language

A compiler is a program which converts high-level language or mid-level language to machine language so that computer can execute the code.


C is very efficient language. The programs written in C are very efficient. Since C was designed for programming UNIX operating system it was crucial that C program could run quickly with the limited amount of memory.


C programs are portable, means that program written in C can run on a different operating system with little or no modification at all.


One of the mosts powerful and flexible operating system was written using C. C is still used to create compiler and interpreters for languages like Python, Perl, PHP, BASIC etc.

Integration with UNIX

C closely ties with Unix and Linux operating system. Most UNIX and Linux system already comes bundled with C compiler called GCC. In fact, there are some tools which require the user to have good knowledge of C.

What kind of applications can be developed using C ?

Anything you want. C language is used to create UNIX, Linux, Windows, Photoshop, Apache Web Server etc.

In the next lesson, we will learn how to install IDE to create and run C programs.