Since the beginning of the British science fiction television series Doctor Who in 1963, many actors have played the title character of The Doctor on television and in various BBC-licensed spin-offs on television, stage, radio, film, audio plays and webcasts. The character's ability to periodically regenerate his appearance and personality has facilitated the ability of new actors to take over the role – in both official and unofficial productions – while in most cases maintaining continuity with the television series.