Known most notably as the resident pianist on the sketch comedy television series The Muppet Show, Rowlf is an anthropomorphic scruffy brown dog of indeterminate breed with a rounded black nose and long floppy ears.

Laid-back and wisecracking, his humor is characterized as deadpan and as such, he is one of few Muppets who is rarely flustered by the show's prevalent mayhem.

Rowlf was created in 1962 being introduced as the spokesman of Purina Dog Chow television commercials aired in Canada, in which he appeared with Baskerville the Hound.

"[6] Dean and Rowlf appeared together for the last time in an episode of The Ed Sullivan Show airing on October 8, 1967, performing "Friendship" while doing the "herd of cows" gag.

Rowlf also played Dr. Bob, the wisecracking doctor in the recurring medical drama parody skit "Veterinarian's Hospital", alongside nurses Janice and Miss Piggy.

Though considered one of the main characters, he rarely interacted with any of the backstage plots involving the show's weekly guest stars.

Although he's only briefly seen, Rowlf had a more prominent role in the behind-the-scenes making-of special that accompanied it, Weezer and the Muppets Go Fishin'.

He also performs "Smells Like Teen Spirit" in a barbershop quartet with Sam the Eagle, Beaker, and Link Hogthrob during the Muppet Telethon, as well as an unwilling (and captive) Jack Black.

A solo album titled Ol' Brown Ears is Back was released by BMG in 1993 and featured 14 songs recorded by Jim Henson as Rowlf.