In mathematics and digital electronics, a binary number is a number expressed in the binary numeral system or base-2 numeral system which represents numeric values using two different symbols: typically 0 (zero) and 1 (one). The base-2 system is a positional notation with a radix of 2. Because of its straightforward implementation in digital electronic circuitry using logic gates, the binary system is used internally by almost all modern computers and computer-based devices. Each digit is referred to as a bit.
| binary (base 2) | base 21 | binary (base 2) | base 21 |
|---|---|---|---|
| 1 | = 1 | 1011 | = b |
| 10 | = 2 | 1100 | = c |
| 11 | = 3 | 1101 | = d |
| 100 | = 4 | 1110 | = e |
| 101 | = 5 | 1111 | = f |
| 110 | = 6 | 10000 | = g |
| 111 | = 7 | 10001 | = h |
| 1000 | = 8 | 10010 | = i |
| 1001 | = 9 | 10011 | = j |
| 1010 | = a | 10100 | = k |
| base 21 | binary (base 2) | base 21 | binary (base 2) |
|---|---|---|---|
| 1 | ≈ 1 | b | ≈ 1011 |
| 2 | ≈ 10 | c | ≈ 1100 |
| 3 | ≈ 11 | d | ≈ 1101 |
| 4 | ≈ 100 | e | ≈ 1110 |
| 5 | ≈ 101 | f | ≈ 1111 |
| 6 | ≈ 110 | g | ≈ 10000 |
| 7 | ≈ 111 | h | ≈ 10001 |
| 8 | ≈ 1000 | i | ≈ 10010 |
| 9 | ≈ 1001 | j | ≈ 10011 |
| a | ≈ 1010 | k | ≈ 10100 |
| binary (base 2) | base 21 |
|---|---|
| 1 | = 1 |
| 10 | = 2 |
| 11 | = 3 |
| 100 | = 4 |
| 101 | = 5 |
| 110 | = 6 |
| 111 | = 7 |
| 1000 | = 8 |
| 1001 | = 9 |
| 1010 | = a |