 Five of the six shorts are played without sound; these shorts are changed from time to time.The sixth short is always Mickey Mouse's 1928 cartoon classic "Steamboat Willie", which is played with its original sound, albeit in an edited version to remove objectionable content; it includes an introduction prepared for a 1950s reissue reminding the viewer when the short was created, and that it is still screening today worldwide.In 2010, for the 55th anniversary of the park, footage of Disneyland's opening day was shown.