A curtain wall is a thinly framed wall of panels connected to a building. Curtain walls do not carry any bearing loads other than gravity and wind. They were first used in medieval castles for protection. They are commonly made with an aluminum framework because of it's light weight. Curtain walls are produced in two types, stick type and unitized. More information about curtain walls can be
. found here http://www.wbdg.org/design/env_fenestration_cw.php.
