List of fictional felines

Cats have often been used as characters in literature and in other forms of media.

Legendary, Mythological and Fairytale cats

Old Possum's Book of Practical Cats by T. S. Eliot, including Macavity, the mystery cat, source of the musical Cats.
"The Black Cat" in Edgar Allan Poe's short story, a study of the psychology of guilt
The Cheshire cat in Lewis Carroll's Alice's Adventures in Wonderland, based on the folk saying, "grinning like a Cheshire cat"
Mehitabel, from archy and mehitabel, a dialogue between a cat and a melancholy cockroach by Don Marquis
The Cat in the Hat by Dr. Seuss
Greebo (in Terry Pratchett novels: see Discworld characters)
The Cat Who Walks Through Walls in Robert A. Heinlein's novel by the same name.
Lillian Jackson Braun writes a lengthy series of mystery novels The cat who... featuring the detective James Qwilleran and his two siamese cats Koko and Yum-yum.
Carole Nelson Douglas writes a series of mystery novels featuring amateur sleuth Temple Barr and her feline companion and fellow investigator Midnight Louie and his daughter Midnight Louise.
Upgraded cats in Reginald Bretnor's "Genius of the Species" take over the Soviet Union

Bill the Cat, mascot and presidential candidate in Berke Breathed's Bloom County
Bagpuss, British TV cat
Courageous Cat, superhero friend of sidekick Minute Mouse
Fatcat
Felix the Cat, pioneer cartoon character
Fritz the Cat, creation of Robert Crumb, changed considerably by Ralph Bakshi in his cartoon, killed later in retaliation by Crumb
Garfield, comic strip character
Heathcliff, comic strip character
Hobbes, Calvin's tiger in the cartoon strip Calvin and Hobbes
Scratchy from the fictional show within a show Itchy and Scratchy in The Simpsons
Snagglepuss, Hanna-Barbera TV cartoon character
Sylvester the cat, cartoon character
Tom, from the cartoon series Tom and Jerry
Top Cat, Hanna-Barbera TV cartoon character
Jess, the cat in the BBC children's TV series Postman Pat
Krazy Kat, surreal cartoon by George Herriman
Fat Freddie's Cat in the Fabulous Furry Freak Brothers by Gilbert Shelton
Pink Panther, movie eponym, cartoon character
Tony the Tiger, commercial spokesman for breakfast food

Schrödinger's cat, hapless victim of a thought experiment illustrating the incompleteness of the theory of quantum mechanics.