What is the musical alphabet on a guitar and how is it used to play different notes and chords?

The musical alphabet on a guitar consists of the notes A, B, C, D, E, F, and G. These notes repeat in higher and lower octaves. To play different notes and chords on a guitar, players press down on the strings at different frets to change the pitch of the notes. By combining different notes and chords, players can create melodies and harmonies in music.