Hank always gets unsolicited emails and he suspects that when those emails are opened, they send a confirmation of it being read. So he disconnects before reading to prevent that from happening. Leo says he never opens spam because he wants to discourage the practice. Spammers often put beacons in messages, which are actually links to invisible image files that are 1 pixel in size. Those images are actually on their servers, so when a message is opened and the image is loaded, it hits their servers. Another way to do prevent senders from getting that information is to turn off HTML in email.