Modulo operation

In mathematics, the modulo operation works out the remainder (what's left over) when we divide two integers (whole numbers without a fraction or a decimal) together. For example, 5 modulo 2 is 1, because if we divide 5 by 2, then we get 2 (because formula_1) with 1 left over. Instead of writing modulo, people sometimes write formula_2. 
Because computers and calculators store numbers in different ways, they sometimes use different steps to work out the modulus (what we get when we modulo two numbers).