Good rhythm guitar players are able to move freely between chords and single notes. To do this well, you need to understand how the notes relate to the chords; and this in turn requires a basic knowledge of music theory. The first step is learning to read music.
There are two methods used to write guitar music: the traditional music notation method (using music notes, 3) and tablature. Both are used in this book but you need only use one of them. Most guitarists find tablature easier to read. However, it is important to learn to read traditional music notation as well. Nearly all sheet music is written in traditional notation. Even if you don’t read well, you will need a basic knowledge of how rhythms are written.