Bert and Ernie
Ernie and Bert are two roommates on the popular U.S. children's television show Sesame Street. The two appear together in numerous skits, forming a comic duo that is one of the centerpieces of the program. Originated by Frank Oz and Jim Henson, the characters are currently performed by Muppeteers Eric Jacobson and Steve Whitmire, with Oz performing Bert occasionally since 2000.
According to A&E's Biography, Ernie and Bert were virtually the only Muppets to appear in the Sesame Street pilot episode, which was screen tested to a number of families in July 1969. Their brief appearance was the only part of the pilot that tested well, so it was decided that not only should Muppet characters be the stars of the show, but would also interact with the human characters, something that was not done in the pilot.