On woven fabrics, the grain line is the warp (the longwise threads which are stretched on the loom), i.e. the longwise direction a fabric. The weft are the threads woven across the warp. On Burda sewing pattern pieces the word grain line (“Fadenlauf” in German) is printed on a suitable straight line or edge. If that is not possible, an arrow with the word “Fadenlauf” indicates the grain line. When placing your paper pattern pieces on your fabric, the grain line or arrow must lie parallel to the selvages (woven edges) of this fabric.