A musical interval is the distance between two pitches, measured in terms of the number of steps or half-steps between them. Intervals can be described as small, like a second, or larger, like a fifth. They are fundamental to music theory, helping to define the relationships between notes in scales and chords. Intervals are categorized into different types, such as major, minor, perfect, diminished, and augmented. Each type has a unique sound and emotional quality, influencing the overall feel of a piece of music. Understanding intervals is essential for musicians when composing, improvising, or analyzing music.