Betacam is a family of half-inch professional videotape developed by Sony from 1982 onwards. All Betacam variants from the original Betacam to Beta SP and Digital Betacam, use the same shape cassettes, meaning vaults and other storage facilities do not have to be changed when upgrading to a new format. The Cassettes comes in two sizes: S & L. The cassette shell and case for each Betacam cassette is colored differently depending on the format, allowing for easy visual identification. There is a mechanical key that allows a video tape recorder to tell which format has been inserted.