The pitches of notes above and below the staff are indicated by short horizontal lines called ledger lines. Here are interactive examples that show the pitches of notes above and below the staff for the bass clef and treble clef.
The pitch letter names A through G keep repeating themselves as throughout the range of each staff. Register is the term we use to describe the relative highness or lowness of the range of a note or group of notes. The treble clef includes notes in higher registers. The bass clef includes notes in lower registers.
Visit the practice page for exercises and assignments on the aspects of sound, and how to draw ledger lines.