Head rails are a type of horizontal element used in curtains and blinds installations. They can also be referred to as valances, top rails, or pelmets. Valances usually have a decorative role and spare the exposure of the hardware components. Top rails are more common and are used to hold the curtain or blind in place while providing support for the moving parts. Pelmets are similar to valances but are more commonly used in formal settings. Other synonyms that can be used to describe head rails include box headers, fascia boards, and cornices. All these terms refer to the same element used primarily to enhance the aesthetics of a window treatment while providing practical benefits.