keyword in c: Keyword is predefined means it is a reserved word which has special meanings and it cannot use as a variable.

keyword in c programming

Use of Keyword in C

There are 32 keywords available in C programming language. Each keyword is used for the different-different purpose.
auto break case char const continue default do
double else enum extern float for goto if
int long register return short signed sizeof static
struct switch typedef union unsigned void volatile while
these all keywords are also called as reserved names. keyword or reserved word makes a language more powerful.
you can learn more details about reserved words available in computer programming and also you can learn about more keywords besides these 32 keywords.