Coatings can be liquid or solid materials; they have been known and used from the time of early man and are of major importance for protecting and decorating the myriad of items in use today. These thin protective films are used to coat commercial and residential buildings (architectural coatings) and for many products in use today (industrial coatings). This article is concerned with the formation of coating films and the properties of these films. Static and dynamic mechanical properties, flexibility, toughness, adhesion, hardness, abrasion resistance, slip, chemical resistance, and stress within coatings are discussed and ways to investigate these characteristics are given. Some of the end-uses and the relationship of coating properties to the uses are detailed