mniip:
in real life we wrote numbers using to numbers: 0,1,2,3,4,5,6,7,8 and 9. when we count we get through all numbers an get back to 0 but then next digit increases
in binary there are only 0 and 1 (ON/OFF)(true/false). when there is 0 we make it 1. if there is 1 we make it 0 but increaze next digit.