How does computer use binary code?

Binary is a counting or numbering system with only 2 symbols - "0" and "1". When ever we count something, we start with nothing or "0". This is an important fact that is common between all numbering systems. We always start with 0 things and add from there. This is important because if all numbering systems didn't have this specific starting point, we could not translate between them.

The way binary works is this: starting with nothing we have "0", then we add one object to get "1". If we add another object, we force an overflow into the next column like this: "12 + 12 = 102" then "102 + 12 = 112"..."112 + 12 = 1002"

This is the same thing that happens in any numbering system. When the symbols are all used in the first column, adding another object forces an overflow into the next higher column of power. In Decimal, we are used to "1010" following 9, as in 9+1. In binary, there are only two symbols, so it overflows to the next higher column rather fast. The following is how we count in binary with four bits (Binary Digits)...

0000

0001

0010

0011

0100

0101

0110

0111

1000

1001

1010

1011

1100

1101

1110

1111

"1111" is the max count for four bits. In order to count another object, we have to use the next higher column... 10000.