Settings => Lookups:
Lookups contains all the types and categories that are reflected inside the project and tasks.
To search for a type, domain or category.
Enter the name in the search tab and click the search button.
The page will show all the domains, types, tasks, groups that contains that name.
Add a type, domain or category:
Click on the domain, type or category you want to add the new option to.
Enter the name in at least one language click on add and it will be added.
Edit type, domain or category:
Click on the edit button.
the name is editable.
Click on save then save I from the lookups page.
The type category or task name changes.