The electric bass guitar (or "electric bass" ; , as in "base") is a bass stringed instrument played primarily with the fingers (either by plucking, slapping, popping, or tapping) or using a pick. The bass is similar in appearance and construction to an electric guitar, but with a larger body, a longer neck and scale length, and usually four strings tuned one octave lower in pitch than the four lower strings of a guitar.

Since the 1950s, the electric bass guitar has largely replaced the double bass in popular music. The bass guitar provides the low-pitched bassline(s) and bass runs in many different styles of music ranging from rock and metal to blues and jazz. It is also used as a soloing instrument in jazz, fusion, Latin, funk, and rock styles.