base 10

     Base ten or base 10 is the system we use for counting--when we get to ten, or a multiple of ten, the numbers "roll over" and we begin a new set of ten. Not to be confused with the metric system--easier to use because it works with multiples of ten, instead of three, twelve, or thirty-six. Base ten means when we get to nine, we add a digit and the next number is twenty, or two tens. We add a digit at one hundred to make ten tens--100.
      There are other "bases", such as base two, used in computing and electronics. Base two "rolls over" at two, which matches an electronic "on" or "off", or the "stripe" or no stripe" of a bar code. In base two, 1=1, 10=2, 11=3, 100=4, 101=5, 110=6, 111=7, 1000=8, 1001=9, 1011=10. An electronic device can read this as "on"--an electrical impulse--or "off"--no electrical impulse. Base two  may seem something like Morse code, except that Morse code had two signals and a "space" or no signal. Base two only has one signal and a "space", or zero.