A tremolo is a bridge that is attached to springs so it can move and change the pitch of the strings.

Only some electric guitars have a tremolo and the best tremolos come with a locking nut which helps keep the strings in tune. The pitch of the strings can only be raised slightly without breaking strings so tremolos are primarily used to lower the pitch.

Certain uses of the tremolo arm have become clichés as they sound quite distinctive. Rather than play a note or chord and then reaching for the tremolo arm, try holding it as you play so you can incorporate it into your playing.