Possible Clues:

• Numbering system using only 1 and 0
• A kind of star system
• Reportedly pared nib back within a year.
• Code whose digits can be translated into letters, eight digits at a time
• Number system with only zeros and ones
• Dispose of a line of 2
• A ____ digit is either 0 or 1
• Using the digits 0 and 1
• The B in NB
• Cutting off end of piece and unravelling yarn in two parts