Explain the modulo division operator in C?

Division is what you expect it to be, the division of two numbers with the result placed somewhere.

Modulus, on the other hand, is the remainder of integer division of two numbers with the result placed somewhere. The modulus function of a and b, a being the dividend and b being the divisor, is a - int(a/b) * b.

For example, using integer results...

47/4 = 11

47%4 = 3

Check it: 47 = 11*4 + 3