The Glossenkeil (Amarna letters), is a form of the common glossenkeil—𒃵 used in the history of cuneiform texts. It is also named a winkelhaken; however the distinct "U" character in cuneiform–-(for the winkelhaken), has multiple uses (see u (cuneiform)), and winkelhakens are composed of the single "u", or a doubled version, one "u" above a second "u".