The Tracey Ullman Show (1987-1990) blended sketch comedy with musical numbers, dance routines, and animated shorts.

Jebediah Springfield founded Springfield in 1796 while looking for "New Sodom" with his partner Shelbyville Manhattan. Springfield & Manhattan went their separate ways & Manhattan went on to found the rival town of Shelbyville.

Almost every episode of The Simpsons shows the Simpson family doing something different as they sit on the couch to watch TV. In some of the opening credits, Bart also writes something different on the blackboard & Lisa sometimes plays a different solo on her saxophone, but the couch segment is often the only one of the three gags to survive the editing room.

In 1990 the "Treehouse of Horror" became an annual tradition of three separate, self-contained stories in each Halloween episode.

Bart Simpson is known for all of these catch-phrases EXCEPT "ha-ha!" which is bully Nelson Muntz's favorite thing to say as he beats up on his schoolmates.

Marge's sisters are Patricia (Patty) Bouvier and the many times married Selma Bouvier Terwilliger Hutz McClure Stu.

Ned owns The Leftorium, which specializes in products for left-handed people. This is a benefit to the surprisingly large proportion of Springfield's left-handed citizens, including Bart Simpson, Principal Skinner, Mr. Burns, and Moe Szyslak.

The Simpsons' current black female cat Snowball is actually Snowball V, but the family renamed her Snowball II to save money on a new dish.

Milhouse Van Houten is one of the few residents in Springfield with eyebrows, a trait he shares with his parents (although in "A Milhouse Divided", it is shown that his mother Luann wears false eyebrows).

In "Homer's Odyssey", Waylon Smithers was accidentally made African American by the color stylist. Smithers' skin tone in this episode was later explained as an "extreme tan".