[Mark T. DeNucci, Sr.]

Originally Posted by JugglingReferee

We all grew up with the decimal system - being taught the numerals from 0 through 9. After 9, a second place value is introduced, and we obtain 10. We've learned how to conduct mathematical operations in this system. Because here are ten symbols (digits), the decimal system is called "base 10".

Computers don't have the luxury of using 10 different representations for anything. Computing operates on voltages. For a computer to run, a constant, although minimal, amount of electricity (voltage) is required. There are only two states in a computer's memory cell or processing "gate": there is either a voltage or there is not. The absense of voltage (not counting the small constant voltage that is required) is referred to as "0" and the presense of voltage is "1".

Therefore, computing has two symbols: 0 and 1. For that reason, it is called "base 2" - or binary. It's numbering system works exactly the same way that base 10 does: when there are no more symbols usable in the first place value, a second place value is created, and so forth.

So, counting is base 2 (called binary) is:

Binary | Decial Equivalent
-------+------------------
.....0 | 0
.....1 | 1
....10 | 2
....11 | 3
...100 | 4
...101 | 5
...110 | 6
...111 | 7
..1000 | 8
..1001 | 9
..1010 | 10
..1011 | 11
..1100 | 12
..1101 | 13
..1110 | 14
..1111 | 15

So... when there's a computer joke that implies only geeks will understand the joke, instead of saying "there are two kinds of people in the world, those who understand the decimal system and those who don't", the nerds say "there are 10 [the binary equivalent of 2] kinds of people in the world, those who panic, and those who Don't Panic".

Jugs:

I still carry my sliderule on my belt in its sheath. Do you? I am glad someone else in this forum understands binary besides me.

MTD, Sr.