# U [GstarCAD 2021](Help%20System/GSTARCAD/2021/Index.md) → [Commands](Help%20System/GSTARCAD/2021/Commands/(Commands).md) ## Topics - **U Command** — [Category](Help%20System/GSTARCAD/2021/Commands/U/U%20Command%20(Category).md) · [Reference](Help%20System/GSTARCAD/2021/Commands/U/U%20Command%20(Reference).md) - [UCAMAN Command](UCAMAN%20Command.md) - [UCS Command](Help%20System/GSTARCAD/2021/Commands/U/UCS%20Command.md) - [UCSICON Command](Help%20System/GSTARCAD/2021/Commands/U/UCSICON%20Command.md) - [UNDEFINE Command](Help%20System/GSTARCAD/2021/Commands/U/UNDEFINE%20Command.md) - [UNDO Command](Help%20System/GSTARCAD/2021/Commands/U/UNDO%20Command.md) - [UNION Command](Help%20System/GSTARCAD/2021/Commands/U/UNION%20Command.md) - [UNISOLATEOBJECTS Command](Help%20System/GSTARCAD/2021/Commands/U/UNISOLATEOBJECTS%20Command.md) - [UNITS Command](Help%20System/GSTARCAD/2021/Commands/U/UNITS%20Command.md) - [UNITS_CLI Command](UNITS_CLI.md) - [UPDATEFIELD Command](Help%20System/GSTARCAD/2021/Commands/U/UPDATEFIELD%20Command.md)