putchar() and getchar() function in C :

getchar() and putchar() are the simplest type of input output function used to perform character input and oputput respectively.

getchar() is a function used to read the character through standard input keyboard.

           Syntax : c = getcher();

putchar() is a function used to display character on the standard output screen.

          Syntax : c = putcher(c);

printf()  and scanf() function in C :

printf() and scanf() are the in built library function in C programming language. Which are available in C by library by default.

printf() is used to print the char, int, string, float, octal, hexa-decimal values onto the output screen.

scanf() is used to read the input from the keyboard given by the user.