The "s" is a little letter that could make a big difference if you're accessing Facebook from an unsecured network like you might find in a cafe or on a school campus. The https protocol encrypts everything you're doing so it's a lot harder to hack into. During the recent upheaval in Tunisia, some protesters were finding that their Facebook accounts had been hacked, possibly by the government. Facebook switched them over to https and the accounts were okay from then on.

We talk with Chet Wisniewski from the security firm Sophos about what the new setting does and what it can protect you from. He says while it's great for stopping outside hackers, it doesn't do much for stopping malicious apps within Facebook itself. So be careful what you click on, be careful what permissions you give.

We also talk to Harlan Yu, a Ph.D student in computer science at Princeton who has done a lot of research on Facebook privacy. He says there are claims that https slows down your computer and that it costs a lot to put on your website. But Harlan says the technology has been around for a while and by this point, the speed difference is almost imperceptible and wouldn't cost much for Facebook to implement it broadly.

So if you want to move to this more secure setting (and both our guests recommend that you do), here's how you do it:

Go to Account Settings, then Account Security and look under Secure Browsing.

Also in this show, a new map shows the swearingest places in America. Shoot!