The idea would be that when you send an email, you give it a category, like politics. Then at the bottom of each person&#x27;s email, there are two links: 1) Unsubscribe from person X&#x27;s emails about category Y, and 2) Unsubscribe from all of person X&#x27;s emails from this system<p>So if that person clicked link #1, the token in the link is verified that it was created for that email address, and then it&#x27;s noted in a database. In the future, if person X sends another email for that category, it won&#x27;t go to that person. I&#x27;m thinking the sender wouldn&#x27;t even know that the person unsubscribed