Pilling refers to those little fuzz balls that collect on the surface of many woven and knit fabrics. It occurs when loose fiber ends escape from their yarn or thread twist. As clothes experience abrasion through normal wear and the agitation of the washing and drying cycles, these loose ends get bound together. Due to the strength of most fabric fibers, these pills are unable to break away from the garment and collect on the surface of your clothes.

Similarly, cotton fabrics can also suffer from pilling effects. Although with the tight weaves of most cotton items, wear most often results in a frayed or fuzzy appearance that can trap dirt and cause colors to look faded.