In 1955, University of Maryland student Jim Henson created a group of puppets for a children's show to air on local TV called "Sam and Friends." The cast of puppets, which Henson called muppets because they combined techniques of puppets and marionettes, included the earliest prototype of Kermit the Frog. The show ran for six years and made Henson a minor celebrity, with appearances on "The Ed Sullivan Show" among others. When the show ended, Henson moved on to commercials.
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