Domain Permission..how does it work?!

Domain Permission..how does it work?!

I've read everything contained in the wiki help, but still I can't figure out how to set this kind of permission for a specfic domain.
For example: I wish to create a wiki, but I don't want it to be public, so that everybody can access it. I just want that a certain number of "users" may see it, but still i don't want to force them to create an account on Zoho( thus creating a very unconvenient situation for zoho, since many users will create an account only to read some info in the wiki and will never contribute to xoho development)

So, I was thinking about DOmani Permission: if I don't understand wrong, with this option I should be able to set a whole group of people who have my same e-mail domain ( for example @mycompany .com ) to have access without registering on zoho.

Is that correct?! And if so...how can i made it?!

As always, thank you very much for your courtesy and for the great job you are taking here!!!