"Sesame Street" first aired in 1969, and has always focused on creativity and thought-provoking content for children taught by Muppets, celebrity guests, videos, and unforgettable songs. It's never slowed down -- and has grown over the decades from a low-budget kids' show to a mini media empire.
"Mister Rogers' Neighborhood" lost its namesake a decade ago, but his spirit is alive and well on PBS -- and got a boost with "The Garden of Your Mind," an autotuned remix of Fred Rogers' singing that's been viewed more than 9 million times (and inspired a slew of other PBS remixes).
Charlie Rose has hosted his namesake news program -- which typically features one-on-one interviews with notable people -- on PBS since 1991.
The weeknight news show "PBS News Hour" is currently anchored by Gwen Ifill and Judy Woodruff. Originally lead by Jim Lehrer and Robert MacNeil, the show first aired in 1975, and was at various times memorably called "The MacNeil/Lehrer Report" and "The MacNeil/Lehrer NewsHour."
"Nova," produced by WGBH Boston, was created in 1974 and has never strayed from its mission of illuminating all things science -- in particular, recent discoveries and cutting-edge theories.
Hosted by artist Bob Ross, "The Joy of Painting" was a half-hour program intended to teach viewers specific techniques of making easy art. After airing for 11 years, the show ended in 1994.
Though new episodes have not been aired since 2008, "Barney & Friends" is still a staple of the 2-5 demo. The purple anthropomorphic Tyrannosaurus Rex may be the butt of many grown-up jokes, but kids still love the songs, dances elementary lessons on how to be a decent human being.
Carl Sagan's "Cosmos: A Personal Voyage" was a 13-part television series that dealt with the origins of life, the universe, and humans' role in it -- for starters. First broadcast by PBS in 1980, it was the most widely watched PBS series in the world at the time.
Built on the foundations of "Sesame Street" and "The Electric Company," LeVar Burton's interactive children's show focused on child literacy, a major issue of its time. It was cancelled in 2006, brought back for reruns through 2008 and was more recently given new life when it became the No. 1 downloaded application on iTunes within 36 hours of its release.
As a long-time partner with PBS, Ken Burns has created and directed several documentaries that stand as seminal works on their respective topics, including "The Civil War," "Baseball," "Prohibition" (pictured above) and "The Central Park Five."
If it weren't for PBS, generations of Americans would never have heard of "Monty Python's Flying Circus" -- brodcasted by BBC from 1969-1974 -- as influential in comedy as the Beatles are in rock 'n' roll.
"Downton Abbey" created a mighty buzz when PBS began airing it in 2011 as part of the Masterpiece Classics.
BBC's modern update of the classic, "Sherlock" is in its third season on PBS. Starring Benedict Cumberbatch as "consulting detective" Sherlcok Holmes and Martin Freeman as John Watson.
A pillar of British pop culture since 1963, the BBC's brainy sci-fi serial "Doctor Who" caught fire in the U.S. when PBS began broadcasting it in the '70s -- it's remained among the network's most popular shows.