thumb|[[Sancho Panza, a squire, can be regarded as a sidekick to Don Quixote in Cervantes' famed fictional work.]]
A sidekick is a close companion or colleague who is, or is generally regarded as, subordinate to those whom they accompany.
Origins
The first recorded use of the term dates from 1896. It is believed to have originated in pickpocket slang of the late 19th century. The "kick" was the front pocket of a pair of trousers, believed to be the pocket safest from theft. Thus, by analogy, a "side-kick" was a person's closest companion.
One of the earliest recorded examples of a sidekick may be Enkidu, who played a sidekick role to Gilgamesh after they became allies in the Epic of Gilgamesh. Other early examples are Achilles and Patroclus in the Iliad and Moses and Aaron in the Old Testament.
In fiction
Sidekicks can fulfill one or multiple functions in fiction, such as a counterpoint to the hero, an alternate point of view, or knowledge, skills, or anything else the hero does not have. They often function as comic relief, A potential example of this is found in the case of the Mario Bros., with Luigi serving in a supporting role to his brother Mario. Sonic the Hedgehog is often accompanied by his sidekick Tails, and his would-be girlfriend Amy Rose also has a hero-sidekick relationship with Cream the Rabbit. Diddy Kong is often seen as the sidekick to Donkey Kong, while Mega Man is aided by his robotic dog Rush.
In comic books
Comic book sidekicks have a long and popular history, dating back to the beginnings of the form. Examples include the Crimson Avenger's sidekick Wing, and Mister America's sidekick Fatman, both of whom debuted in the late 1930s. Other notable comics sidekicks include Ebony White, Jughead, Etta Candy, Captain Haddock, and Obelix.
In 1940 DC Comics introduced comics' first teenage sidekick, Robin, created to soften the dark tone of the Batman comics and make the Dark Knight more attractive to younger readers. Robin's instant popularity spawned a host of imitations, including such iconic characters as Bucky, Toro, Sandy the Golden Boy, and Speedy. Stripesy was the exception to the rule: an adult sidekick to a teen hero, the Star-Spangled Kid. Another unusual sidekick pairing was the Blonde Bomber (Honey Blake), a newsreel camerawoman, chemist, and crime-fighter with a male sidekick named Jimmy Slapso.
The prevalence of adult superheroes and their teenage "wards" caused some observers to look askance at the trend. Psychologist Fredric Wertham decided that the phenomenon was a landmine of hidden Freudian issues, and that a sidekick's participation in violent encounters alongside his hero masked a sexual subtext.