用於移除物件和更正錯誤的指令

Commands

CUTCLIP (指令)
ERASE (指令)
MREDO (指令)
OOPS (指令)
OVERKILL (指令)
PURGE (指令)
REDO (指令)
REDRAW (指令)
UNDO (指令)

System Variables

UNDOCTL (系統變數)
UNDOMARKS (系統變數)
COMMANDPREVIEW (系統變數)