Polyester (aka Terylene) is a category of polymers which contain the ester functional group in their main chain. Although there are many forms of polyesters, the term "polyester" is most commonly used to refer to polyethylene terephthalate (PET). Other forms of polyester include the naturally-occurring cutin of plant cuticles as well as synthetic polyesters such as polycarbonate and polybutyrate.Polyester may be produced in numerous forms. For example, polyester as a thermoplastic may be heated and processed into different forms and shapes, eg: fibres, sheets and three-dimensional shapes. While combustible at high temperatures, polyester tends to shrink away from flames and self-extinguishes. This book provides leading edge research on this field from around the globe.