I have a lot of unknowns in my family tree. While The Master Genealogist genealogy computer program is amazingly powerful, it requires that you have set a mother or father of a person before you can use the ADD PERSON feature to connect a brother or sister. I often find brothers and sisters with no mention of a parent, and I want that information in my database. So I type in “unknown” for the name.

However, Terry of Terry’s TMG Tips recommends leaving the names blank:

While some like to enter their preferred term in place directly in the name field in order to control how they will appear in the Picklist, I do not recommend that approach. I find that I can deal with the blank names in the Picklist just fine, and find the flexibility of being able to globally control how names appear in reports much more useful. If you enter a term you like directly in name tags and later decide you would like a different term, you may have hundreds or perhaps thousands of tags to change. But if you leave the unknown names blank, you can change how all of them will appear in reports with a simple change to the report settings. You can even have them appear differently in different reports (TMG 5 and later).
Terry of Terry’s TMG Tips - Leave the Unknown Names Blank

He recommends that if you have to use the ADD PERSON function in TMG, do so and type in whatever you want. Then edit the name field and remove the name, leaving it blank afterwards. Simple and easy.