Intervals
An interval is the distance between two notes. The smallest interval on most instruments is a half-step, also called a semitone. This is one fret on the guitar, or from a black note to the next white note on the keyboard/piano.

Absolute beginners don't need to learn all the intervals, but you will want to learn some pretty early on so you can learn to play along to recordings. The first intervals a beginner should learn are the Perfect 4th, and Perfect 5th. Thats 5 half-steps for Perfect 4th, and 7 half-steps for P5.

Here are the whole lot: They all have their own feeling, so play them and explore!!

Interval name	Abbreviation	Number of half-steps	Example
minor 2nd	m2	1	C - Db
Major 2nd	M2	2	C - D
minor 3rd	m3	3	C - Eb
Major 3rd	M3	4	C - E
Perfect 4th	P4	5	C - F
diminished 5th	dim5	6	C - Gb
Perfect 5th	P5	7	C - G
Augmented 5th	Aug5	8	C - G#
Major 6th	M6	9	C - A
minor 7	m7	10	C - Bb
Major 7th	M7	11	C - B
Perfect Octave	P Oct	12	C - C

A Major interval made smaller by a semitone/fret becomes a minor interval. Note the use of capital 'M' for Major, and lower case 'm' for minor. This is a convention. Maj7 is Major 7. m7 is minor 7.

This means that the interval of 8 semitones/half steps/frets could have two name. An Augmented 5th (C to G#), and a minor 6th (C to Ab).

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