SingleBit

A single bit, or bit, is the most basic unit of information in digital systems. It encodes one of two possible states, commonly denoted 0 and 1. Bits are stored and manipulated using physical media such as electrical voltages, magnetic states, or optical signals. In digital circuits, they are processed by logic gates that implement basic operations including AND, OR, XOR, and NOT; combinations of bits form larger data structures such as bytes and words.

From an information-theory perspective, a single bit conveys up to one bit of information when the outcome is uncertain, with maximum entropy of 1 bit for a fair binary variable.

Operations on bits lie at the heart of computing. Bitwise operators, shifts, and masking allow programmers and circuits to implement algorithms, data encoding, and control logic.

Single-bit errors are a concern in storage and communication. Parity checks and error-correcting codes, such as Hamming codes, are designed to detect and/or correct errors that flip a single bit.

Data is typically organized into bytes (eight bits) and larger units. Historically, some systems used seven-bit bytes, but modern architectures generally use eight-bit bytes and wider word sizes.

The term bit derives from binary digit and became widely used with the rise of digital electronics and information theory in the mid-20th century.

Related topics include bit, byte, parity, and Hamming codes.