Television’s longest running half-hour scripted series is “The Simpsons.”

The groundbreaking animation first hit the air Dec. 17, 1989, but the family first appeared on television in “The Tracey Ullman Show” short “Good Night” on April 19, 1987.

As a tribute to the long lasting show, FXX kicked-off a Simpsons marathon Thursday. It will run through Labor Day, showing all 552 episodes, uncut.

The marathon began with the very first episode, “Simpsons Roasting on an Open Fire.” It will conclude at midnight Sept. 2nd with the airing of the season 25 finale, The Yellow Badge of Cowardice.

Even the film “The Simpsons Movie,” will air in the middle of the marathon at 6 p.m. Eastern Time, Aug. 29.

In honor of the show’s lasting power, here are the all-time top five best characters in the show’s history.

5. Lisa Marie Simpson

Lisa may have had the most evolution since the show began. She went from being just a smart kid who snitched on her brother to being the moral compass of not just the family, but all of Springfield. And she loves Jazz.

4. Robert Underdunk Terwilliger, PhD. AKA Sideshow Bob

Krusty the Clown’s sidekick is voiced amazingly by Kelsey Grammer, and he first appeared in the episode “The Telltale Head.” Bob is a self-proclaimed genius who is a graduate of Yale University, a member of the Republican Party, and a champion of high culture. He became the arch nemesis of Bart and tried to murder him several times over. An adult attempting to kill a kid wasn’t normal subject matter for most cartoons in the 1990s. But “The Simpsons” writers somehow made it funny.

3. Bartholomew JoJo ‘Bart’ Simpson

Initially Bart was the antihero. Catchphrases such “Eat my shorts,” “¡Ay, caramba!”, and “Don’t have a cow, man!” made him a favorite for the kids and easy target for conservatives who believed he was the root for the downfall of the American family. A T-shirt reading “I’m Bart Simpson. Who the hell are you?” was banned in several public schools. He was the character who initiated most of the storylines. But as the show became more mainstream, he became less and less controversial, mostly because the things he was doing didn’t compare to the trouble real life kids were getting into.

2. Mo Szyslak

The town bartender with the temper was the favorite not-Simpson on the show. According to an ABCnews.com poll, “Moe is a clear favorite of the writers, a sad, lonely man with a rag that the series loves to rag on. He further increases his screen time with a subtle history of showing up at the Simpson household, flowers in hand, ready to step in and replace Homer as Marge’s man after a stressful family situation.”

1. Homer Jay Simpson

When the show first began, Homer had taken a backseat to the antics of his son Bart. But as “The Simpsons” progressed, he was the figure that began to become the face of the show. From his love of donuts and beer to his ability to make dumb decision turn out right, Homer was seen as the only real American dad on television.