It is a library file which is included in the program this is used to use

Clrscr ( )

getch ( )

getchar ( ) etc.

We do not need to include this file in C program. It is necessary for C++ programs. Conio stands for CONsole Input Output header file.

Math .h

This file is used for mathematical functions. These functions are like excel functions:-

Eg. pow( ), sqrt ( ), sin ( ), tan ( ) etc.