Pattern paper has code numbers to indicate its weight from heavy to light:
Heavy-weight Paper - Weight Code
Heavyweight pattern paper is called tag board, manila, or hard paper and is used primaily for production patterns.
Light-weight Paper - Weight Code 1 to 5 Double-Duty Marking Paper
Lightweight paper is called marking paper.
Marking paper is used for making markers and to develop first patterns.
The paper is marked with a choice of symbols and numbers, letters, short lines, and/or dots. The symbols help when aligning the grainlines of the patterns for tracing, andthe numbers give and account of inches of the finished marker.
Color-coded paper (color on one side only) has two functions: to indicate right-side-up of the pattern pieces and/or to indicate the design division to which the patterns belong.