The Key of a Song
Any song that you play will be in a certain key (sometimes switching between more than one key). If a song is in the key of C major, then you know that any notes in the scale of C major will fit into the song. The notes in a C major scale are C, D, E, F, G, A, and B. Let’s say a song in the key of C major progresses through with the chords C, D, and G. You can emphasize these root notes when these chords are played while using other notes in the scale of C major to transition between these chords. As long as you are playing in C major, the notes will fit.