"Sesame Street" is the longest-running children's show in US history.

The first episode ran on November 10, 1969, at the height of the civil rights movement and the War on Poverty. It introduced the world to Big Bird, Cookie Monster, Oscar the Grouch and other beloved characters.

The idea was to harness the power of television to help young children, especially those less advantaged, prepare for school.

Over the years, the educational show has taught children not only the alphabet and how to count, but how to peacefully resolve conflict, treat others with respect and deal with loss.

It can now be seen in more than 150 countries, in 70 different languages.

Puppeteer Jim Henson poses with some of his creations, including Kermit the Frog, Bert and Ernie. "Sesame Street" was created by television producer Joan Ganz Cooney and Lloyd Morrisett, a psychologist who was vice president of the Carnegie Foundation for the Advancement of Teaching. They brought on Henson and his colorful Muppets to help bring the show to life.
Puppeteer Jim Henson poses with some of his creations, including Kermit the Frog, Bert and Ernie. "Sesame Street" was created by television producer Joan Ganz Cooney and Lloyd Morrisett, a psychologist who was vice president of the Carnegie Foundation for the Advancement of Teaching. They brought on Henson and his colorful Muppets to help bring the show to life.
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The show frequently has celebrity guest stars, such as actor James Earl Jones. Jones was the first celebrity to appear on the show. <a href="index.php?page=&url=https%3A%2F%2Ftwitter.com%2Fsesamestreet%2Fstatus%2F531895624602374144" target="_blank" target="_blank">He recited the alphabet</a> during an episode in 1969.
The show frequently has celebrity guest stars, such as actor James Earl Jones. Jones was the first celebrity to appear on the show. He recited the alphabet during an episode in 1969.
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From left, puppeteers Daniel Seagren, Jim Henson and Frank Oz rehearse for a "Sesame Street" episode in 1970.
From left, puppeteers Daniel Seagren, Jim Henson and Frank Oz rehearse for a "Sesame Street" episode in 1970.
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Actor Matt Robinson, the first actor to play Gordon on the show, chats with Cookie Monster.
Actor Matt Robinson, the first actor to play Gordon on the show, chats with Cookie Monster.
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Football quarterback Joe Namath plays with children on the "Sesame Street" set in 1972.
Football quarterback Joe Namath plays with children on the "Sesame Street" set in 1972.
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Did you know Oscar the Grouch was originally orange? Here he is with puppeteer Caroll Spinney in 1970.
Did you know Oscar the Grouch was originally orange? Here he is with puppeteer Caroll Spinney in 1970.
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Someone makes an adjustment to Spinney's Big Bird costume while he is in it in 1970. In full costume, Big Bird is more than 8 feet tall.
Someone makes an adjustment to Spinney's Big Bird costume while he is in it in 1970. In full costume, Big Bird is more than 8 feet tall.
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Bert and Ernie, seen here in 1976, have been old pals since the beginning. Fun fact: Bert has an identical twin brother named Bart. Bart made a brief appearance in an episode in 1974.
Bert and Ernie, seen here in 1976, have been old pals since the beginning. Fun fact: Bert has an identical twin brother named Bart. Bart made a brief appearance in an episode in 1974.
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Michael Jackson, the "King of Pop," hangs out with Oscar the Grouch on a "Sesame Street" Christmas special in 1978.
Michael Jackson, the "King of Pop," hangs out with Oscar the Grouch on a "Sesame Street" Christmas special in 1978.
Sesame Workshop/Everett Collection
Cookie Monster runs for president in 1976. He promised that if people voted for him, there would be a cookie in every pot. Oscar was his campaign manager.
Cookie Monster runs for president in 1976. He promised that if people voted for him, there would be a cookie in every pot. Oscar was his campaign manager.
Sesame Workshop/Everett Collection
Sesame Street was designed to resemble an inner-city neighborhood. Its name, inspired by the phrase "Open Sesame" from "Ali Baba and the Forty Thieves," is credited to writer Virginia Schone. It was decided on at the last minute, and <a href="index.php?page=&url=https%3A%2F%2Fwww.sesameworkshop.org%2Fwho-we-are%2Four-history%2Fhow-sesame-street-got-its-name" target="_blank" target="_blank">there were initial concerns</a> that young children would have trouble pronouncing it.
Sesame Street was designed to resemble an inner-city neighborhood. Its name, inspired by the phrase "Open Sesame" from "Ali Baba and the Forty Thieves," is credited to writer Virginia Schone. It was decided on at the last minute, and there were initial concerns that young children would have trouble pronouncing it.
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"Sesame Street" actor Bob McGrath rehearses for an episode in 1970.
"Sesame Street" actor Bob McGrath rehearses for an episode in 1970.
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The Rev. Jesse Jackson, right, talks with executive producer Jon Stone on the "Sesame Street" set. Jackson recited the poem "I Am - Somebody."
The Rev. Jesse Jackson, right, talks with executive producer Jon Stone on the "Sesame Street" set. Jackson recited the poem "I Am - Somebody."
Children's Television Workshop/Everett Collection
Oscar the Grouch chats with actor Will Lee, who played Mr. Hooper on the show. When Lee died in 1983, the show didn't replace him with a new actor. Instead, it used the moment to teach children about death.
Oscar the Grouch chats with actor Will Lee, who played Mr. Hooper on the show. When Lee died in 1983, the show didn't replace him with a new actor. Instead, it used the moment to teach children about death.
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Ray Charles plays music with Bert and Ernie on a "Sesame Street" episode in 1977. Charles appeared on numerous episodes throughout his life.
Ray Charles plays music with Bert and Ernie on a "Sesame Street" episode in 1977. Charles appeared on numerous episodes throughout his life.
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Frank Oz holds Bert and Jim Henson holds Ernie during a rehearsal in 1970.
Frank Oz holds Bert and Jim Henson holds Ernie during a rehearsal in 1970.
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Richard Polsky, a National Educational Television researcher, tests the attention span and reaction of a 4-year-old boy watching "Sesame Street." The show used educational experts to help craft its curriculum.
Richard Polsky, a National Educational Television researcher, tests the attention span and reaction of a 4-year-old boy watching "Sesame Street." The show used educational experts to help craft its curriculum.
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