Comments are a way of explaining what makes a program. Comments are ignored by the compiler and used by others to understand the code.
C language has a collection of functions that can be used in a program with required number of arguments written in parentheses. it is to be noted that arguments are nothing but constants/variables/expression. Input/Output functions are also included in the user program by using the header file <stdio.h> which stands for standard input-output header.
The main() is the main function where program execution begins. Every C program must contain only one main function.
Note : int/void main() int/void is a return value, which will be explained in a while.
scanf() : function is used to read input values of variables using the standard input device.
printf() : function is used to print display value of variables using the standard output device.