Interval degrees describe the number of scale steps from the **Tonic** (scale's 1st step).

For example, a **Major 3rd** interval, represents the distance of the **3rd** scale degree away from the Tonic:

Major 3rd

1st

2nd

3rd

4th

5th

6th

7th

1st

In the same way, a **Perfect 5th** interval, represents the distance of the **5th** scale degree away from the Tonic:

Perfect 5th

1st

2nd

3rd

4th

5th

6th

7th

1st

Any of the basic intervals (within the 1st octave), can be extended by an octave or more.

For instance a **Major 2nd** interval can be extended by an octave, to become a **Major 9th**.

In the next few lessons we will go over the basic intervals up to an Octave.