The ukulele originated in the 19th century as a Hawaiian interpretation of the cavaquinho or braguinha and the rajão, small guitar-like instruments taken to Hawaiʻi by Portuguese immigrants. It gained great popularity elsewhere in the United States during the early 20th century, and from there spread internationally.

The tone and volume of the instrument varies with size and construction. Ukuleles commonly come in four sizes: soprano, concert, tenor, and baritone.