Short answers, pulled from the story.
Excluding zoomusicological instruments and the human voice, the percussion family is believed to include the oldest musical instruments. Striking an object to produce sound requires no construction beyond finding something to hit, making percussion accessible before strings or wind instruments could be developed.
Percussion instruments can belong to four organological classes: idiophones, membranophones, aerophones, and chordophones. Idiophones vibrate through their entire body, membranophones through a struck membrane, chordophones through struck strings, and plosive aerophones through a column of air set in motion by impact.
Definite pitch percussion instruments, such as the marimba, timpani, xylophone, and vibraphone, produce a clear fundamental pitch and can play melody and harmony. Indefinite pitch instruments, such as the snare drum, bass drum, and crash cymbals, produce such complex overtones that no single pitch is discernible.
The Hornbostel-Sachs system has no high-level section for percussion as a category. Most percussion instruments are classified as idiophones and membranophones within that system. The term percussion appears only at lower levels of the hierarchy, used to describe instruments struck with a non-sonorous object such as a hand, stick, or striker.
Edgard Varèse used air-raid sirens in Ionisation, and Tchaikovsky scored cannon fire in the 1812 Overture. Krzysztof Penderecki called for a hammer and saw in De Natura Sonoris No. 2. Rock band Aerosmith used shotguns, brooms, and a sugar bag in Sweet Emotion, while Slipknot is known for hitting baseball bats against beer kegs.
A djembe player is called a djembefola, a dunun player a dununfola, and a steelpan player a panman or pannist. A güirero plays the güira, a Dominican scraper used in merengue music. A bongocero plays bongos and typically also the cencerro, a type of cowbell.