Ska stroke

The ska stroke or ska upstroke, skank or bang, is a guitar strumming technique that is used mostly in the performance of ska, rocksteady, and reggae music. "Reggae is most easily recognized by...the skank." Ska strokes serve as a rhythmic base to a song, and may be doubled by the drums. This style of playing has a dance associated with it, the skank. In reggae, the guitar usually plays a short, percussive, "scratchy chop sound [chord]," on beats 2 and 4 (1 2 3 4), often supported by staccato piano (late 1960s to the early 1980s) or synthesizer. Play 

Ska strokes create a bouncing rhythm, going up then down in pitch. Played in 4
4 time (...
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