A vibrato system on a guitar is a mechanical device used to temporarily change the pitch of the strings. It adds vibrato to the sound by changing the tension of the strings, typically at the bridge or tailpiece of an electric guitar using a controlling lever, which is alternately referred to as a whammy bar, vibrato bar, or tremolo arm. The lever enables the player to quickly and temporarily vary the tension and sometimes length of the strings, changing the pitch to create a vibrato, portamento, or pitch bend effect. Instruments without a vibrato have other bridge and tailpiece systems.
The pitch-bending effects have become an important part of many styles, allowing creation of sounds that could not be played without the device, such as the 1980s-era shred guitar "dive bomb" effect.
