Because not all of the 12 notes sound good together, we must select a set of notes to use in a song. This is a Key.
When a song says that it is in the key of C Major or D Minor this is simply telling you which of the 12 notes are used in this song.
That's it.
Seven notes from the Chromatic Scale. The 1st, 3rd, 5th, 6th, 8th, 10th, and 12th intervals. It then repeats back from 1. This is one of the most common keys in music. Click the notes to play them.
Remember, the frequency of the starting note doesn't matter. The Major scale will always have these intervals.
Again, seven notes from the Chromatic Scale. The 1st, 3rd, 4th, 6th, 8th, 9th, and 11th intervals. It then repeats back from 1. This is also a very common Key.
There are many other keys, but these two are the most common. We'll save the other keys for a later lesson.
Here's a little tool to help you find the notes in any Key. Notice how the pattern never changes. Instead we just shift where we begin our Key pattern.