Quadrupedalism is a form of land animal locomotion using four limbs or legs. An animal or machine that usually moves in a quadrupedal manner is known as a quadruped, meaning "four feet" (from the Latin quad for "four" and ped for "foot"). The majority of quadrupeds are vertebrate animals, including mammals such as cattle, dogs and cats, and reptiles, like lizards.

Birds, humans, insects, crustaceans, and snakes are not quadrupeds. However, there are some exceptions. For example, among the insects, the praying mantis is a quadruped. A few birds may use quadrupedal movement in some circumstances, for example the shoebill will sometimes use its wings to right itself after lunging at prey.

Not all four-limbed animals are quadrupeds. Although arms and wings are, in the evolutionary sense, modified legs, four-limbed vertebrates are in fact classed as tetrapods, members of the taxonomic unit Tetrapoda. These include all vertebrates with quadrupedal ancestors, including mammals, reptiles, amphibians, and birds.

Daniel Robert "Danny" Elfman (born May 29, 1953) is an American composer, best known for scoring music for television and film and creating The Simpsons main title theme as well as the 1989 Batman movie theme. He was the lead singer and songwriter for the rock band Oingo Boingo, from 1976 to 1995. He has scored the majority of the films for his long-time friend Tim Burton.

Born in Los Angeles, he entered the film industry in 1976, initially as an actor. He made his film scoring début in in 1980 for the film Forbidden Zone directed by his older brother Richard Elfman. He has since been nominated for four Academy Awards and won a Grammy Award for Tim Burton's Batman and an Emmy Award for his Desperate Housewives theme. Elfman was honored with the prestigious Richard Kirk award at the 2002 BMI Film and TV Awards. The award is given annually to a composer who has made significant contributions to film and television music.

Elfman was born in Los Angeles, California, the son of Blossom Elfman (née Bernstein), a writer and teacher, and Milton Elfman, a teacher who was in the Air Force. Elfman grew up in a racially mixed community in the Baldwin Hills area of Los Angeles. He spent much of his time in the local movie theatre, adoring the music of such film composers as Bernard Herrmann and Franz Waxman.