Hammer-on

A hammer-on is a playing technique performed on a stringed instrument (especially on a fretted string instrument, such as a guitar) by sharply bringing a fretting-hand finger down on to the fingerboard behind a fret, causing a note to sound.

Passages in which a large proportion of the notes are performed as hammer-ons and pull-offs instead of being plucked or picked in the usual fashion are known in classical terminology as legato phrases.

The sound is smoother and more connected than in a normally picked phrase, due to the absence of the necessity to synchronize the plucking of one hand with the fingering on the fingerboard with the other hand; however, the resulting sounds are not as brightly audible, precisely due to the absence of the plucking of the string, the vibration of the string from an earlier plucking dying off.

A hammer-on is usually represented in guitar tablature (especially that created by computer) by a letter h. A rapid series of alternating hammer-ons and pull-offs between a single pair of notes is called a trill.

The term hammer-on was first invented and popularized by Pete Seeger in his book How to Play the 5-String Banjo.