Television pilot, usually called just a "pilot", is a test episode made to sell a television series. It may be broadcast as the first episode if the series is sold to a network or cable channel, and sometimes has different actors or other differences to the real series. There are also many series whose pilot episodes are titled ""Pilot"". While many pilots are made, few make it to the screen, and even fewer go on to become full television series because of big competition between networks and producers. There are many types of television pilots. Some pilots are put on other shows first to start the show. These are called "backdoor pilots". An example of a backdoor pilot is "Gloria: The First Day" is an episode in "Archie Bunker's Place" but is used to start "Gloria". A "put pilot" is a pilot that a network agrees to put on television and if they do no they have to pay a lot of money to the television studio. An "unsold pilot" is a pilot episode that are made by a studio but are not put on television. 