Facebook is the most popular site on the planet and, contrary to appearances, it's also one of the most private. It's a preferred target for random hackers and people you know who may have a reason to get ahold of your account.
Unfortunately, most people do little to protect their Facebook accounts, even though the site actually offers a decent amount of protection.
The biggest thing you can do to improve your security is enabling two-step or two-factor authentication. The feature, as the name suggests, adds another step to the login process, besides the password, you're also going to need a code.
Google and others make the feature an option and it's a very good idea to enable it wherever possible. Facebook has supported the feature for more than a year now.
The big problem was actually getting the code; for a long time, the only way was to have it sent to your phone via SMS. That sounds good in theory, but in practice it didn't really work.
Problems with Facebook or carriers meant that the message would take hours to arrive or fail to arrive at all, making the feature useless and worse, leaving you with no way to sign into your account.
But that changed last summer when Facebook built a password code generator into the Android app. This meant that you didn't have to rely on the SMS to arrive, you could simply use the app to generate a code and use it anywhere you needed it.
Since then, Facebook has built the code generator into the iPhone and iPad apps as well. Still, plenty of people don't know it exists or how to use it, so here's a short guide.
1. Go to the Facebook settings > the Security tab
2. Click on "Edit" next to the "Login Approvals;"
3. Tick the box next to "Require a security code…"
4. You'll need to provide a phone number if you don't have one already;
5. You'll then be sent a confirmation code to your phone, use that to activate the feature;
6A 1. Alternatively, if you don't get an SMS, you can use the Facebook app if you have it installed already;
6A 2. In the Facebook app, tap the menu button, scroll down to "Account" and tap "Code Generator;"
6A 3. Use the code there to finalize Login Approvals on your desktop.
6B 1. If you don't have the Facebook app installed or haven't configured the Code Generator there, click on the "Set up Code Generator" link;
6B 2. Follow the instructions provided to install the app and activate the Code Generator;
6B 3. Hit "Finish Setup" and you should be done.