Fancy yarn is a type of yarn that is different from the classical yarn structure, produced by changing the raw material used, production, and material properties, giving different effects, making it contain decorative irregularities in terms of color or form.

Fancy yarns are yarn types that are produced in different forms according to the fashion of the day, with a predominant appearance and aesthetic aspect in addition to the yarn structure.Fancy yarns with different structures that cannot be compared with normal yarns have been developed in order to obtain fabrics with more visual features. Fancy  yarns have an important place in the developing textile industry and ever-changing fashion trends, thanks to its almost limitless pattern possibilities. It is seen that new types of yarns are added to this group every passing day. Special technologies, creativity, and design techniques are used in the production of fancy yarn .