# U Command [GstarCAD 2018](Help%20System/GSTARCAD/2018/Index.md) → [Commands](Help%20System/GSTARCAD/2018/Commands/(Commands).md) → [U](Help%20System/GSTARCAD/2018/Commands/U/(U).md) - [U](Help%20System/GSTARCAD/2018/Commands/U/U%20Command%20(Reference).md "U") - [UCS](Help%20System/GSTARCAD/2018/Commands/U/UCS%20Command.md "UCS") - [UCSICON](Help%20System/GSTARCAD/2018/Commands/U/UCSICON%20Command.md "UCSICON") - [UCSMAN](Help%20System/GSTARCAD/2018/Commands/U/UCAMAN.md "UCSMAN") - [UNDEFINE](Help%20System/GSTARCAD/2018/Commands/U/UNDEFINE%20Command.md "UNDEFINE") - [UNDO](Help%20System/GSTARCAD/2018/Commands/U/UNDO%20Command.md "UNDO") - [UNION](Help%20System/GSTARCAD/2018/Commands/U/UNION%20Command.md "UNION") - [UNISOLATEOBJECTS](Help%20System/GSTARCAD/2018/Commands/U/UNISOLATEOBJECTS%20Command.md "UNISOLATEOBJECTS") - [UNITS](Help%20System/GSTARCAD/2018/Commands/U/UNITS%20Command.md "UNITS") - [UPDATEFIELD](Help%20System/GSTARCAD/2018/Commands/U/UPDATEFIELD%20Command.md "UPDATEFIELD") ---