Desert Island Discs is a long-running BBC Radio 4 programme. It was first broadcast on 29 January 1942 and is said by the Guinness Book of Records to be the longest-running music programme in the history of radio. Celebrity guests are invited to imagine themselves castaways on a desert island, and to choose eight pieces of music to take with them. In the same manner, Last.fm users can tag recordings as "desert island discs" to indicate their own favourite pieces of music. .