|A ground (core) component, an effect component and a binder are three principle of fancy yarn. To obtain structural effect, longer length of effect component, relative to ground component must be present to form the required effect. Twisting of the effect component on to the ground component will produce aesthetic effect. The basic principle is therefore to feed the ground and effect component at different speeds in to the twisting element. The percentage ratio of the effect component to the ground component is called over feed ratio.