Base 10
We normally count in a base 10 form. That means we go through 10 numbers before we start over and add another digit. 0,1,2,3,4,5,6,7,8,9 or 00,01,02,03,04,05,06,07,08,09 We start back at 0 with the number 10. and add a number to the 10s digit with the 1. We then continue and go through the same 10 numbers again.

Base 2
In a binary Base 2 system, there are only two numbers: 0,1. We go through only 2 numbers before starting over. 0, 1, 10, 11, 100, 101, etc. or 000, 001, 010, 011, 100, 101. Computers and Digital Circuits use a base 2 system because it is easier to determine between two numbers as opposed to 10 numbers.
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