A bit is the basic unit of information in computing and digital communications. A bit can have only one of two values, and may therefore be physically implemented with a two-state device. These values are most commonly represented as either a . The term bit is a portmanteau of binary digit.

.bit is a top-level domain that was created outside the most commonly used Domain Name System (DNS) of the Internet, and is not sanctioned by the Internet Corporation for Assigned Names and Numbers (ICANN). The .bit domain is served via the cryptocurrency, Namecoin infrastructure, which acts as an alternative, decentralized domain name system. Use of the .bit domain requires a copy of the Namecoin blockchain, a supporting public DNS server, or a web browser plug-in.

A bit is a unit of information storage on a computer.