In broacasting and radio communications, a call sign (also known as a callsign or call letters, or abbreviated as a call, or otherwise known as a handle) is a unique designation for a transmitting station. In some countries they are used as names for broadcasting stations, but in many other countries they are not. A call sign can be formally assigned by a government agency, informally adopted by individuals or organizations, or even cryptographically encoded to disguise a station's identity.