Allegro is a musical term that means to play quickly and cheerfully. When you see allegro written at the top of sheet music, it tells the musician to perform that piece at a brisk, lively tempo, usually faster than walking pace but not as fast as running.

The word comes from Italian, where it originally meant “cheerful” or “lively.” In music, allegro combines speed with energy and brightness. Think of the difference between sprinting away from something scary and running joyfully across a field on a beautiful day. Allegro is the second feeling.

Many famous classical pieces include allegro movements. The first movement of Mozart's Eine kleine Nachtmusik is marked allegro, giving it that bouncy, spirited quality that makes people want to tap their feet. Beethoven's Fifth Symphony opens with an allegro con brio (allegro with vigor), creating that famous urgent, dramatic mood.

Musicians learn allegro alongside other Italian tempo markings like adagio (slowly) and andante (at a walking pace). These words help composers communicate not just speed but the emotional character they want in their music. When a pianist plays allegro, they're bringing both quickness and joy to the performance.