Maracas are simple percussion instruments (idiophones), usually played in pairs, consisting of a dried gourd shell (cuia - 'kOO-ya') filled with seeds or dried beans. They may also be made of leather, wood, or plastic. Often one maraca is pitched high and the other low.

The instrument is of prehistoric American origin. The word maraca is thought to have come from the Tupi language of Brazil, where it is pronounced 'ma-ra-KAH'.

Maracas are heard in many forms of Latin American music and are also used in pop and classical music. The are considered characteristic of the music of Colombia, Venezuela, and Brazil. In rock and roll, they are identified with Bo Diddley.

Although a simple instrument, the method of playing the maracas is not obvious. Because the seeds must travel some distance before they strike the gourd to make a sound, the player cannot shake them on the beat, but must anticipate the beat.

Related instruments include the Cuban guiro, and the caxixi- 'ka-shee-SHEE' and ganza- 'gan-ZAH'.