 In very simple cases, knitting can be done without tools, using only the fingers to do these tasks; however, hand-knitting is usually carried out using tools such as knitting needles or rigid frames.Depending on their size and shape, the rigid frames are called knitting boards, knitting rings (also called knitting looms) or knitting spools (also known as knitting knobbies, knitting nancies, or corkers).Other tools are used to prepare yarn for knitting, to measure and design knitted garments, or to make knitting easier or more comfortable.