Five lines and four spaces make up the staff. Each line and space symbolizes a distinct letter (A-G), which corresponds to a different note. When it comes to assigning the note names A-G on the staff, the order is determined by the clef. The treble clef is used for notes played in music written in the key of C, while the bass clef is used for notes played in music written in the key of G. For other keys, adjust the clefs accordingly. Thus, the lines on the staff represent the notes of the scale; each line has a unique name corresponding to a specific note. For example, the first line above middle C represents the note D. The second line represents E, the third F, and so on. Notes that fall on the same line but are separated by spaces are called groups of notes. Thus, the three notes D, E, and F form one group. Notes that fall on different lines but are adjacent to each other are called neighbor notes. The notes G and C are neighbors, as are the notes B and F. However, the notes A and G are not since they don't belong to the same scale degree (they're both half steps away). Staff notation also shows us how to play certain notes.