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PDP-6 flip-flop stores one bit 1
Bit,
the basic unit of information in information theory and computing - a binary digit, either 0 or 1 in the arithmetical sense, 'false' or 'true' in the boolean sense, black (dark) or white (light) as a Color in Chess, etc..
Quote
by Claude Shannon in A Mathematical Theory of Communication 1948 1:
The choice of a logarithmic base corresponds to the choice of a unit for measuring information. If the base 2 is used the resulting units may be called binary digits, or more briefly bits, a word suggested by J. W. Tukey. A device with two stable positions, such as a relay or a flip-flops circuit, can store one bit of information.
Aggregations
Aggregations of bits are used to code numbers, integers or floating point values, characters, codes and sets. Four bits are called a Nibble with 16 states - written as one hexadecimal digit {'0'..'9', 'A'-'F'}. A group of eight Bits, two Nibbles or one Byte with 256 states (e.g. unsigned numbers 0..255) is most often the smallest addressable unit in computer architectures. Bitboards are set-wise bit aggregations which covers all 64 squares of a Chessboard.
Bitwise Arithmetic
Bitwise addition (Modulo 2) and subtraction with aggregations of Bits without overflows can be applied by bitwise exclusive or:
| a | b | a xor b |
|---|---|---|
| 0 | 0 | 0 |
| 0 | 1 | 1 |
| 1 | 0 | 1 |
| 1 | 1 | 0 |
See also
External Links
- Bit from Wikipedia
- Bit (disambiguation) from Wikipedia
- Nat (information) from Wikipedia
- Ban (information) from Wikipedia
- Qubit from Wikipedia
- shannon (unit) from Wikipedia
- Bits by Lawrence J. Krakauer
References
Claude Shannon (1948). A Mathematical Theory of Communication, pdf reprint↩︎