Computers are based on a binary number system or a base-2 system. The only two numerical symbols are 0 and 1, which are electronically stored as off or on states. Decimal or base-10 orders of magnitude are powers of 10 (1, 10, 100, 1000, ...), but binary or base-2 orders of magnitude are powers of 2 (1, 2, 4, 8, 16, ...).
| Binary | Decimal |
| 00000000000 | 0 |
| 00000000001 | 1 |
| 00000000010 | 2 |
| 00000000100 | 4 |
| 00000001000 | 8 |
| 00000010000 | 16 |
| 00000100000 | 32 |
| 00001000000 | 64 |
| 00010000000 | 128 |
| 00100000000 | 256 |
| 01000000000 | 512 |
| 10000000000 | 1024 |
| 01111101000 | 1000 |
| 01111111111 | 1023 |
10 bits (binary digits) can represent 1024 different values or memory addresses from 0 (000000000) to 1023 (1111111111). For a computer, 1024 is a nice round number, while 1000 is not.
Date: 2008-04-09 |
