Grain

Direction in which most of the fibers of machine-made paper are lying. The direction is important if paper is to be folded or rolled. It will fold more easily and smoothly along the grain. 2 methods of determining grain are firstly, to bend the paper in half, noting how much it resists bending: and secondly, to tear the paper. Handmade paper may be folded indiscriminately, as it has no grain. Its fibers are lying evenly in all directions. (Rose Folsum)