by Jason AnkenyThe most successful animated family in television history, the Simpsons were the brainchild of cartoonist Matt Groening, previously best known for his work on the weekly comic strip Life Is Hell. The Simpsons -- buffoonish father Homer, nervous mother Marge, juvenile delinquent son Bart, brainiac daughter Lisa, and toddler Maggie -- first appeared in brief "bumper" segments on the Fox network variety series The Tracey Ullman Show, later graduating to a 1989 Christmas special and finally, in 1990, their own weekly series. Based on Groening's own family -- ten-year-old Bart, the name an anagram of "brat," served as the cartoonist's proxy -- The Simpsons was an immediate ratings smash, and suddenly the characters' licensed images were everywhere from T-shirts to action figures; an LP proved inevitable, and in 1990 the Geffen label issued The Simpsons Sing the Blues, scoring a novelty hit with the single "Do the Bartman." Music played an essential role in the series, and many prominent performers agreed to supply their voices for guest roles; in addition to appearances from acts including U2, Smashing Pumpkins, Aerosmith, and the Red Hot Chili Peppers, all three surviving Beatles even contributed voiceovers. While a second LP, The Yellow Album, was planned, and even recorded for a 1993 release, it sat on the shelves until late 1998; in the interim, Songs in the Key of Springfield -- a collection of themes and musical interludes composed by the program's musical director, Alf Clausen -- was issued in 1997. A sequel, Go Simpsonic with the Simpsons, followed two years later. A full decade later, The Simpsons Movie, a soundtrack penned by Hans Zimmer coincided with the Simpsons' first feature film.