Cloth has a selvage on the two sides of the cloth. The salvage is a straight raveling

Woven fabrics have two grain lines one runs parallel to the selvage the other runs 90 degrees to the selvage.

Most patterns for woven fabric will have a dibble pointed arrow. When cutting the pattern this arrow is to be placed parallel to the selvage.

all the pieces are arranged in the same direction. The reason for this is that fabric looks different when light hits it from different direction. If one of the pieces to be cut was upside down it may look like the project was made from 2 different color cloth.