Signal (disambiguation)

A signal is any variation of a medium that conveys information.

Signal or signaling may refer to:

Science and technology

SIGNAL (programming language), a synchronous programming language
Signal (software), an encrypted voice calling, video calling and instant messaging app
- Signal Protocol, a cryptographic protocol used by the Signal application
Signal (IPC), a form of inter-process communication used in Unix and related operating systems
- C signal handling, a way for handling signals received by programs during their execution

International Code of Signals, a standard for sending signals by displaying flags
- Maritime flag signalling, generally flaghoist signalling, by which ships communicate with each other
- Naval flag signalling, covers various forms of flag signalling, such as semaphore or flaghoist
Military communications, often called "signals"
Recognition signal in human, technical or biological communications
Signaling (telecommunications), a part of some communication protocols
Smoke signal, an ancient form of communication
Telegraphic signal, in telegraphy

Signal (magazine), a Wehrmacht propaganda magazine which was published in occupied Europe during World War II
SIGNAL (US magazine), publication of the Armed Forces Communications and Electronics Association
Signal, a New York Yiddish-language literary monthly published from 1933 to 1936 by the Communist Party USA
Signal (novel), a 2009 children's novel about a boy who helps a girl from another planet signal her parents
Signal (South Korean TV series), a 2016 South Korean police procedural TV series
Signal (Japanese TV series), a 2018 Japanese police procedural TV series based on the 2016 South Korean series of the same name
Signal – The Southeast Electronic Music Festival, an annual music festival held in the US
Signal, Wyoming, a fictional town from the 2005 film Brokeback Mountain

Signal (bridge), a permitted means of conveying information to partner through the play of cards in contract bridge
Signalling (economics), in economics theory
Citation signal, in law
Signal (toothpaste)
Signal Systems, a telecommunications company of the McLean Group of Companies
Signal Foundation, a non-profit organization
USS Signal, several US Navy ships