Programme Identification (PI) is a service provided by radio stations transmitting Radio Data System (RDS) data as part of the FM radio broadcast. The PI code allows the radio to display the name of the radio station - for example BBC Radio 1.
RDS receivers decode the extra data contained within the FM radio signal to display extra information on compatible radio receivers.
This information could include the name of the station, information about the programme's output - e.g. song titles, contact details (e.g. telephone numbers) or the current time.
In addition to this information which the listener can see, RDS also allows listeners to stay tuned to a network whilst travelling across the service area of multiple transmitters. It also allows listeners to a particular network to benefit from cross-network travel news services, traffic flashes and for the flagging of travel-related programming.
The PI Code is also used by the RadioDNS standard.