What are intervals?

Intervals are a specific distance between two notes in music. They are used to describe the relationship between two pitches, and are classified by their size (e.g. major, minor, perfect, augmented, diminished). Intervals are an important concept in music theory and are used to build chords, scales, and melodies.

In music theory, intervals are the distance between two musical notes. Intervals can be measured horizontally or vertically, and can be either melodic or harmonic.

- Melodic intervals occur when two notes are played in succession, one after the other.
- Harmonic intervals occur when two notes are played simultaneously.

Intervals are classified according to their size, which is determined by the number of semitones between the two notes. The semitone is the smallest interval in Western music, and is equal to one half step on the piano keyboard.

The basic intervals are:

- Unison (0 semitones) - two notes that sound exactly the same
- Minor second (1 semitone) - two notes that are very close together, such as C and C#
- Major second (2 semitones) - two notes that are slightly further apart, such as C and D
- Minor third (3 semitones) - two notes that are somewhat close together, such as C and Eb
- Major third (4 semitones) - two notes that are more distant, such as C and E
- Perfect fourth (5 semitones) - two notes that are fairly distant, such as C and F
- Tritone (6 semitones) - two notes that are very distant, such as C and F#
- Perfect fifth (7 semitones) - two notes that are quite distant, such as C and G
- Minor sixth (8 semitones) - two notes that are somewhat close together, such as C and Ab
- Major sixth (9 semitones) - two notes that are slightly further apart, such as C and A
- Minor seventh (10 semitones) - two notes that are somewhat close together, such as C and Bb
- Major seventh (11 semitones) - two notes that are more distant, such as C and B
- Octave (12 semitones) - two notes that sound exactly the same, but at a different pitch