After playing through each major scale, you may have noticed that some of the keys have a lot of sharp (#) symbols … while others have a lot of flat (b) symbols. For example, check out the B major scale, which has a total of five (count ‘em … 5) sharp symbols:

Seriously, can you imagine playing an entire song in the key of B? With all those extra symbols—which are called “accidentals”—cluttering up the staves, music notation would start to look a little scary. And, honestly, that would be a problem.

So, to work around this issue, musicians came up with a little something they call “key signatures” … which basically keep the staves tidy by listing all the sharp or flat symbols once—next to the clef signs. For example, the key signature for the key of B simply lists all five sharps (#) of the major scale before the notes … so we can focus on the notes themselves.

It’s pretty basic, really. And the nice thing is—all key signatures work in this same way. For example, the C major scale doesn’t have any sharps or flats … so its key signature is empty. But the key signature for G has one sharp (F#) … while the key of D has two sharps (F# and C#) … and the key of A has three sharps (F#, C#, and G#) … and so on. Every key signature simply lists the sharps or flats of a given major scale.

By listing all these symbols next to the clef, we can clean up the staves and keep the sharps and flats out of the way. So anytime we need to play a sharp or flat note, we already know about it by looking to the key signature at the beginning of the staff.

Of course, with Color Music, we can easily tell which note is which—even without any sharps or flats. So, for us, key signatures are useful … but really just for knowing which key to play. In other words, key signatures give us a heads up on which notes we’ll come across in a song or melody.

To get a feel for how the key signatures work, try playing through each major scale below. Only this time, we’ll use key signatures. Nothing has changed about these 12 note patterns. It’s just that everything looks simpler now … like we’ve swept all those extra symbols to the side so we can really focus on the notes.