Charlie Brown, the American cartoon character who fails in almost everything he does. He always keeps an enthusiasm that things might go okay, but they never do. In fact, often his misfortune is orchestrated or taken advantage of by his peers.
The comic strip he appeared in was called "Peanuts" which has a lot more characters. Charlie has a dog, who is almost as famous as he is - Snoopy - A white beagle who doesn't talk. Oh, and there was also a little bird, who was Snoopy's best friend - called Woodstock. In fact they were all enjoyable characters - such as Linus with his shock of unruly hair and dirty blanket, or the teachers who never spoke properly - only in an incoherent muffled mumble.
Created by Charles M Shultz, the cartoon was first published in 1950, but the cartoons were still as popular as I was growing up in 1980. The character of Charlie Brown
It was eventually made into an animated cartoon as well, which seemed to play continuously when I was younger.
Obviously there have been many toy tie-ins such as cuddly Snoopy's or the other characters as well.
He's probably one of the most enduring characters in animation still around, though there have been no new strips since February 13th, 2000, when the creator passed away the day before that strip was published.