__Qualities and Size__
Intervals can be described as Major (M), Minor (m), Perfect (P), Augmented (A), and Diminished (d).

Intervals come in various sizes: Unisons, Seconds, Thirds, Fourths, Fifths, Sixths, and Sevenths.

2nds, 3rds, 6ths, and 7ths can be found as Major and Minor.

Unisons, 4ths, 5ths, and Octaves are Perfect.

So
let's look at the Chromatic Scale:

C, C#, D, D#, E, F, F#, G, G#, A, Bb, B, C

C to C# is a Minor second

D to D is
a Major second

C to D# (also called Eb) is a Minor Third

C to E is a Major third (we use these a lot)

C to F is a
Perfect 4th

C to F# is a Diminished 5th

C to G is a Perfect 5th

C to G# is an Augmented 5th

C to A is a Perfect
6th

C to Bb is a Minor 7th

C to B is a Major 7th

C to C is an Octave

(it continues on after the octave to 9th,
10th, etc.

I hope that clears up some of the confusion and gives you some ideas on how to go about using the software to
recognize the intervals.

Listen to some intervals here.