Cosmo Kramer, usually referred to simply by his surname, is a fictional character in the American television sitcom Seinfeld (1989–1998) played by Michael Richards.

Kramer is the neighbor of the series' main character, Jerry Seinfeld, and is friends with George Costanza and Elaine Benes.

His character is that of a lovable rogue with his trademarks being his upright hairstyle, vintage wardrobe, impractical business ideas and eccentric personality, whose combination led Elaine to characterize him as a "hipster doofus".

His antics include frequent pratfalls and a penchant for noisy, percussive outbursts to indicate skepticism, agreement, irritation and a variety of other feelings.

A profile in The New York Times described Kramer as "cartoon-like" in a piece with a headline calling him "Seinfeld's craziest neighbor".

[5] This was the original reason behind why Kramer helps himself to Jerry's possessions and food without any pushback and also why he is absent from the season two episode "The Chinese Restaurant", which takes place entirely outside of the building.

In "The Kiss Hello" Elaine tries to take advantage of this personality quirk by inviting Kramer to meet her friend, Wendy, whose hairstyle she feels is outdated.

However, Kramer is also quick to assume the worst of Jerry, believing him guilty of everything from sabotaging a Miss America contestant (in "The Chaperone") to having a double life as a neo-Nazi leader (in "The Limo"), and is often oblivious to his sentiments.

Oftentimes, the "experiments" never happen due to Kramer's inherent short-attention span, including his plan to eliminate all furniture and build "levels... like ancient Egypt" in "The Pony Remark".

Inside views of Kramer's apartment are seldom seen, but it's known that he installed hardwood flooring and woodgrain-like wallpaper to, as he explains to Jerry, "give it the feel of a ski lodge."

Kramer's conversation sometimes contains onomatopoeia or nonsensical sounds in order to stress an emotional point or describe earlier actions.

This was later parodied in "The Pilot" when the actor that is cast to play him in Jerry and George's sitcom refuses to base the character on the real Cosmo Kramer.

George finds out his first name of "Cosmo" through an encounter with Kramer's long estranged mom, Babs, in "The Switch".

He is a compulsive gambler who successfully avoids gambling for several years until "The Diplomat's Club", in which he bets with a wealthy Texan on the arrival and departure times of flights going into New York's LaGuardia Airport.

A struggling (and terrible)[7] actor, Kramer's first gig was a one-line part in a Woody Allen movie in "The Alternate Side" (his line, "These pretzels are making me thirsty", becomes the show's first catchphrase).

Kramer later works as a stand-in on a soap opera with his friend Mickey Abbott in "The Stand In" and various other low-paying or non-paying theater projects, such as acting out illnesses at a medical school in "The Burning".

Kramer shows an entrepreneurial bent with "Kramerica Industries", for which he devises plans for a pizza place where customers make their own pie ("Male Unbonding"), a bladder system for tankers that will "put an end to maritime oil spills" ("The Voice"), and a product that will put ketchup and mustard in the same bottle.

In "The Friar's Club", he creates a concept restaurant that only serves peanut butter and jelly sandwiches, which he calls P.B.

In "The Doorman", Kramer and Frank Costanza co-develop a prototype for a bra for men called the "bro" or the "manssiere".

The money Kramer makes allows him to briefly retire to Florida and run for president of the condo board at Del Boca Vista, Phase 3.

In "The Foundation", he takes on a group of kids at a karate school, and in "The Van Buren Boys", after giving his stories to Elaine to write, he slips up on the golf balls and lands on the floor.

Pennypacker in "The Puerto Rican Day", Kramer poses as a prospective buyer interested in an elegant apartment in order to use its bathroom.

In "The Nose Job", Kramer uses the pseudonym Professor Peter Von Nostrand to pose as the betrothed son-in-law of an incarcerated man who once stole his jacket in order to retrieve it from the man's apartment; Kramer's jacket, to which he attributes at least some of his amorous success, is a minor plot point in other episodes until, in "The Cheever Letters", he trades it to a Cuban embassy official for several boxes of authentic Cuban cigars.

As Dr. van Nostrand, Kramer tries to get hold of Elaine's medical chart to erase the negative comments her doctor has made in "The Package".

He also uses the van Nostrand alias in the episode "The Slicer", posing as a "Juilliard-trained dermatologist" for a cancer screening at George's company, Kruger Industrial Smoothing.

Kramer uses the name Martin van Nostrand (without the "doctor" title) while auditioning for the role of himself on the show Jerry in "The Pilot, Part 1".

Kramer is also occasionally called "the K-Man" ("The Barber", "The Bizarro Jerry", "The Busboy", "The Note", "The Hamptons", "The Scofflaw" and "The Soup Nazi").

A derogatory designation for Kramer has been "hipster doofus", a moniker assigned to him by a woman in a wheelchair he once dated in the episode "The Handicap Spot", and occasionally directed at him by Elaine, as in "The Glasses".

[11] Ken Tucker wrote in a 1992 review in Entertainment Weekly that Kramer is "the most cartoonish, least-defined person in Seinfeld.

Kramer is an earnest dope whose long, gangly body always seems to surprise his mind — he's always running, stumbling, bumping into things; he doesn't enter Jerry's apartment so much as he explodes into it.