Tremolo is a musical technique that involves the rapid repetition of a single note or the quick alternation between two notes. It creates a wavering or shaking sound, adding expressiveness to music. Tremolo can be produced on various instruments, including the guitar, violin, and piano, and is often used in both classical and contemporary compositions. In addition to its use in live performance, tremolo can also be achieved electronically through effects pedals or software. This technique is commonly found in genres like rock, classical, and blues, enhancing the emotional impact of a piece by creating a sense of movement and intensity.