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Option
Result
Categories
Establishes a category for each To Do task you create. For example, marketing, finance, and so on.
Priority
Establishes a priority or uses no priority (default) for each To Do task you create.
Completed on
Lets you specify or not specify (default) the date you completed the To Do task.
Confidential
Makes or doesn't make (default) the To Do task confidential, so others accessing your file can't view it.
If you assigned a password to your file, only the Owner can see and change entries that are confidential.

See also:

Working with categories
Assigning a category to an entry