A Charlie Brown Christmas
A Charlie Brown Christmas is an animated holiday special based on the Peanuts comic strip by Charles Schulz. Originally airing in 1965 on CBS (where it aired until 2000, before switching to present network ABC in 2001), it was the first of many animated specials based on the strip, and has since gone on to become one of the most successful, popular, and enduring animated specials in history.
Written by Schulz himself, and directed and animated by Bill Melendez, A Charlie Brown Christmas was a groundbreaking piece of television in many ways. The young characters were voiced by actual children, something that had not been done before that point. Another major point of departure from the orthodoxy of the day was the absence of a laugh track; Schulz believed that the audience was capable of figuring out when to laugh. 
Despite its iconic status today, A Charlie Brown Christmas was not without controversy at the time it was created. Network executives strongly opposed Schulz's decision to have Linus quote from Luke 2:8-14. Schulz, however, was adamant, as the scene was crucial to the show's theme (Charlie Brown's search for the true meaning of Christmas amid a flood of commercialism). Executive producer Lee Mendelson later recalled telling Schulz that "...you can't read from the Bible on network television"; both he and Bill Melendez worried that the show would be a failure. 
Mendelson's concerns proved unfounded. When it first aired on December 9, 1965, A Charlie Brown Christmas ranked number 2, with a rating of 28.8 and 46.6 per share. In other words, nearly half of the people watching television were watching the special. 
- Mendelson, Lee. It's The Great Pumpkin, Charlie Brown: The Making of a Television Classic. New York: Harper, 2006.