cross window= rectangular window divided info four by a mullion and a transom, sash window= made up of two parts that slide up and down, traditional style of windows in UK, casement window= this type of window swings in or out like door, common in the USA and Europe, bay windows= extend outwards from the main walls of a building, popular in Britain, stained glass window= composed by pieces of coloured glass divided by lead glazing bars, very popular in Victorian houses in England