Duet = a piece that is played by two instruments.
Free Stroke = a motion of the right hand fingers or thumb where they move over the next string after playing it.
Ledger Lines = helplines above or under the music staff.
Rhythm = the part of music that deals with tempo and time.
Rhythmic pattern = a reoccurring group of notes.
Scale = notes that moves step-like up or down the staff.
Tie = two or more notes that are joined together by a curved line of which only the first of these notes is played.