title: Sign (disambiguation)
text: # Sign (disambiguation)
  
  A sign is an entity which indicates another entity.
  
  Sign may also refer to:
  
  ## Communication
  
  * Signage, the use of signs and visual graphics to convey information
  * Signature, a handwritten depiction of someone's name or other mark used as a proof of identity and intent
  * Sign (semiotics), anything that communicates a meaning
  * Sign language, a languages that uses the visual-manual modality to convey meaning
  
  ## Mathematics
  
  * Sign (mathematics), an indication of negative and positive numbers
     * Sign function, also known as the signum function
     * Sign of a permutation of a finite set
  
  ## Organizations
  
  * Project Sign, a project by the U.S. Air Force to investigate unidentified flying objects (UFOs)
  * Servicio de Inteligencia de la Gendarmería Nacional or Inteligencia de la Gendarmería Nacional Argentina, the Argentine intelligence service
  * Scottish Intercollegiate Guideline Network, a Scottish group that develops evidence-based medical guidelines
  
  ## Music
  
  * Sign (band), an Icelandic band
  * Sign (Clock DVA album), 1993
  * "Sign" (Mr. Children song), 2004
  * "Sign" (Beni Arashiro song), 2010
  * "Sign" (Flow song), 2010
  * "Sign", a 2018 song by Exo from Don't Mess Up My Tempo
  * "Sign", a 2001 song by Marcella Detroit from Dancing Madly Sideways
  * "Sign", a song by Susumu Hirasawa
     * "Sign-2", a different version of "Sign" from Berserk: Millennium Falcon Hen Seima Senki no Shō
  * Sign (Autechre album), 2020
  * "The Sign" (song), a 1993 song by Ace of Base
  * The Sign (Ace of Base album), a 1993 album by Ace of Base
  
  ## Surname
  
  * Christopher Sign (1976–2021), American journalist
  
  ## Other uses
  
  * Astrological sign, one of twelve sectors of the sky in astrology
  * Medical sign, an indication of disease, injury, or abnormal physiological state
  * Sign (TV series), a 2011 South Korean television series
  