A wind instrument is a musical instrument that creates sound when a player blows air into or across it. The moving air makes the air inside the instrument vibrate, producing musical notes. Flutes, clarinets, trumpets, trombones, tubas, saxophones, and oboes are all wind instruments.

Wind instruments work in different ways. With a flute, you blow across an opening, like blowing across the top of a bottle. With a clarinet or saxophone, you blow through a thin piece of wood called a reed that vibrates rapidly. With a trumpet or trombone, you buzz your lips against a metal mouthpiece. Despite these differences, they're all wind instruments because air is what makes the sound.

Players change notes by covering and uncovering holes with their fingers, or by pressing valves that change which tubes the air flows through. The longer the column of air inside the instrument, the lower the note. That's why a piccolo (very short) plays high notes while a tuba (very long) plays low, rumbling notes.

The woodwind and brass families in an orchestra are both types of wind instruments. Recorders, harmonicas, bagpipes, and even pipe organs are wind instruments, too.