newid() question

when you use newid() is that a new uniqueidentifier for the database or for the table?

I have a changelog that captures newly created users first and gives them a newid, then i want to approve that change and copy the newid generated for that user into the user table. Will I run into duplicate id's that way?The NEWID() function creates aGUID. This number should be, statistically-speaking, unique.