Originally Posted by
thebat
So I buy 5 day ticket for WDW. I swipe my finger the first day I use it? Than, the rest of the day I swipe it again as I enter the park again? Than, the next day I enter, I must swipe again and it must match the print from the previous day? Or is the data erased daily?
Sorry if this is basic but I really don't know what's going on with the fingerprinting.

The finger swipe attaches biometric info permanently to your ticket so it can't be used by anyone else, or sold to other people at a discount.