In music

Music

Music is an art form whose medium is sound and silence. Its common elements are pitch , rhythm , dynamics, and the sonic qualities of timbre and texture...

, a drum stroke is a note performed on percussion instrument

Percussion instrument

A percussion instrument is any object which produces a sound when hit with an implement or when it is shaken, rubbed, scraped, or otherwise acted upon in a way that sets the object into vibration...

s known as a drum

Drum

The drum is a member of the percussion group of musical instruments, which is technically classified as the membranophones. Drums consist of at least one membrane, called a drumhead or drum skin, that is stretched over a shell and struck, either directly with the player's hands, or with a...

. There are four basic strokes.

The Full Stroke begins with the tip of the drumstick held 8-12" above the striking surface. The drummer strikes the drum and then returns the stick back up to its original position.
The Down Stroke begins with the tip at the same height as the full stroke, but upon striking the drum head, the drummer keeps the stick low (about an inch above the striking surface).
The Up Stroke begins with the tip of the stick hovering about an inch above the head of the drum. The drummer strikes the surface, then brings the stick up to full stroke or down stroke position.
In the Tap, the stick begins at the same position as the up stroke and remains there after striking.

The four strokes are used in concert with one another to produce a variety of accented and unaccented beat combinations.