# ATTDEF Command
[GstarCAD 2020](Help%20System/GSTARCAD/2020/Index.md) → [Commands](Help%20System/GSTARCAD/2020/Commands/(Commands).md) → [A](Help%20System/GSTARCAD/2020/Commands/A/(A).md)
The ATTDEF command is used to save data attribute definition in block.
## Command Access:
> **Ribbon:** Home \> Block  \> Define Attribute
> **Ribbon:** Insert \> Block Definition \> Define Attribute
> **Menu:** Draw \> Block \> Define Attributes...
> **Command:** ATTDEF (display Attribute Definition dialog box), -ATTDEF (display command line prompts)
## Function Description:
> 
>
> The attribute of block could be contained in block definition. Users could save data in attribute, such as number of parts, product name, etc.
> Inputting “-attdef” under the command prompt, it will display options.
## Other versions with matching text
[GstarCAD 2016](../../../2016/Commands/A/ATTDEF%20Command.md) · [GstarCAD 2017](../../../2017/Commands/A/ATTDEF%20Command.md) · [GstarCAD 2018](Help%20System/GSTARCAD/2018/Commands/A/ATTDEF%20Command.md) · [GstarCAD 2019](Help%20System/GSTARCAD/2019/Commands/A/ATTDEF%20Command.md) · [GstarCAD 2021](Help%20System/GSTARCAD/2021/Commands/A/ATTDEF%20Command.md)