unit backspace character(UBS)
A word processing formatting control that moves the printing or display point to the left one escapement unit as defined to provide character alignment in proportionally spaced text.; 一種文字處理格式控制符,在按比例隔開的正文中,把打印點或顯示點左移一個規定的移位單位來對齊字符.參閱backspace character