Vibrato & tremolo are often used in the guitar world and the two words are used interchangeably at times, and many feel confused about their meanings. In this short article, we'll discuss how to describe the two terms and their history.
Vibrato
Vibrato means the rapid changes in the pitch (frequency) of a note. It has been used for centuries as a technique for adding expression to music.
Tremolo
Tremolo means a trembling effect produced by slight and rapid changes in the volume (amplitude) of a note.
In short, vibrato deals with change in pitch while tremolo deals with change in volume. And the current tremolo system in the guitar market should be vibrato system.
History Mistake
When Fender invented their synchronized tremolo system, which is actually a vibrato system, they marketed it as tremolo mixed up these two terms, and never corrected it. That's why many manufacturers started to use the term tremolo to refer to vibrato.