- fundamental unit of information, a binary digit: 0 or 1
- coined by Claude Shannon in his 1948 paper founding information theory
- Shannon entropy: H = -sum(p * log2(p)), measured in bits
- 8 bits = 1 byte, the standard addressable unit of computer memory
- kilobit, megabit, gigabit, terabit: network speeds measured in bits per second
- a fair coin flip carries exactly 1 bit of information
- quantum computing uses the qubit, a superposition of 0 and 1
- data compression aims to reduce the number of bits needed to represent a message
- all digital computation reduces to operations on bits: AND, OR, XOR, NOT