Sound is a type of energy that travels in waves through the air, water, or solid materials. When an object vibrates, it creates pressure waves that our ears can detect. For example, when you strum a guitar, the strings vibrate, producing sound waves that travel to your ears, allowing you to hear music. Different sounds have unique qualities, such as pitch and volume. Pitch refers to how high or low a sound is, while volume indicates how loud or soft it is. Instruments like the piano can produce a wide range of pitches, making them versatile for creating various musical styles.