Cuíca, or "kuweeca", is a Brazilian friction drum with a large pitch range, produced by changing tension on the head of the drum. The tone it produces has a high-pitched squeaky timbre.

This instrument was originally used in Africa for lion hunting due to the fact that the sound produced by a cuica can be very similar to a lion female roar, thus attracting the male (other say Cuíca is Portuguese for a type of small opossum which is known to make a high-pitched sound..).

It was brought to Brazil by Afran slaves (probably Bantu') where is nowadays very popular and commonly used at Carnival time by the Escolas de Samba.

Metal cuica is the most common one but it can be made by wood or rarely (view pic) by fiberglass.
Embedded on the underside of the calf-skin head is a bamboo stick.

The cuica's sound is produced by pulling and pushing a wet cloth on the bamboo stick. By pressing the head with the finger close to the center it is possible to change the sound (the harder you press, the higher the sound will be). 

The cuíca is used to accompany a variety of different folk and urban popular dances. For example, it may be part of the instrumental ensemble for the May dança de Santa Cruz or for the moçambique dramatic dance (bailado) in Minas Gerais. It also is used in Holy Cross dances and processions and in performances of São Paulo rural sambas.

The cuíca plays an important rhythmic role in samba music of all kinds. It is particularly notable as a fixture of Rio de Janeiro's Carnival groups, which feature entire sections of cuíca players. It is so commonly used in radio-oriented samba music that in the absence of a cuíca player, Brazilian singers or other musicians imitate the sound of the cuíca with their voices.

An example of this imitation can be heard on the intro part of Dizzy Gillespie's version of Chega de Saudade (from the "Dizzy on the French Riviera" album, 1965) composed by Antonio Carlos Jobim. Along with samba, the cuíca is one of the mainly used Brazilian instruments in jazz-rock, free jazz, and Latin jazz.

CREDITS
Thanks to Wikipedia for part of the instrument description