Silicon are a class of materials with unique properties that make them useful in a variety of applications of commercial interest and support a thriving global industry. This article updates a comprehensive survey of the chemistry and technology of silicones last published in Kirk‐Othmer Encyclopedia of Chemical Technology in 1997. The update contains more than 235 references not cited in the previous version and includes literature published through 2001. A new section dealing with fiber finishing applications has been included in the current version. The review provides an excellent primary reference for this interesting area of chemistry and technology.