> For the complete documentation index, see [llms.txt](https://alphamoon.gitbook.io/documentation/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://alphamoon.gitbook.io/documentation/user-guide-how-tos/supervision/how-to-open-and-edit-a-table-mask.md).
# How to open and edit a table mask?
A step-by-step guide
See what possibilities table mask gives you. Let's jump straight in!
### What is a mask?
The role of the mask at Alphamoon Workspace is to indicate in the document where the table is located as well as what structure it has.
### Open table mask
If you want to open the table mask simply click on the chosen table field from the extraction list:
Table mask
### Edit table mask
Double-click on the mask to go to the editing mode:
Table mask
You can **edit your table mask** by:
* Changing headers
* Adjusting table columns and rows
Once you finish editing your table mask, click the **Done** button below the table in the document viewer to make sure all your changes are successfully saved.
#### See next:
