Signal, signals, signaling or signalling may refer to:

Science

Computing

  • C signal handling, a way for handling signals received by programs during their execution
  • SIGNAL (programming language), a synchronous programming language
  • Signal (software), an encrypted voice calling and instant messaging application developed by Open Whisper Systems
  • Signal Protocol, a non-federated cryptographic protocol that provides end-to-end encryption for instant messaging conversations
  • Unix signal, a limited form of inter-process communication used in Unix, Unix-like, and other POSIX-compliant operating systems

Communications

Transportation

Music

Albums

Songs

Arts and entertainment

Other uses