What You Can’t Do on Facebook
Facebook is meant to represent real people and real associations; it’s also meant to be safe. Many of the rules of participation on Facebook exist to uphold those two goals.
There are things you can’t do on Facebook other than what's listed here. For example, you can’t send multiple unsolicited messages to people you’re not friends with; you can’t look at the photos of someone who has really tight privacy settings; you can’t spin straw into gold. These rules may change how you use Facebook, but probably won’t change whether you use it.
You can’t lie on Facebook
Okay, you can, but you shouldn't, especially not about your basic information. Lying about your identity is a violation of the Statement of Rights and Responsibilities and grounds for your Timeline being disabled. Although many people try, Facebook doesn’t let anyone sign up with an obviously fake name like Fakey McFakerson. Those who do make it past the name checks will likely find their account flagged and disabled.
You can’t be twelve and be on Facebook
Or younger. Seriously. Facebook takes very seriously the U.S. law that prohibits minors under the age of 13 from creating an online Timeline for themselves. This rule is in place for the safety of minors, and it's a particular safety rule that Facebook does enforce. If you’re reported to the Facebook User Operations team and they confirm that you’re underage, your account will be disabled.
You can’t troll or spam on Facebook
On the Internet, trolling refers to posting deliberately offensive material to websites in order to get people upset. Spamming refers to sending out bulk promotional messages. If you do either of these things on Facebook, there’s a good chance your account will be shut down.
The logic for this is that Facebook is about real people and real connections. It’s one thing to message a mutual friend or the occasional stranger whose Timeline implies being open to meeting new people if the two of you have matching interests. However, between Facebook’s automatic detection systems and user-generated reports, sending too many unsolicited messages is likely to get your account flagged and disabled.
Similarly, Facebook aims to be a trusted environment for people to exchange ideas and information. If people deliberately disturb the peace with pornographic, hateful, or bullying content, that trust is pretty much broken.
Chances are that you have no intention of spamming or trolling, so keep in mind that if you see either of these things happening, you can report the content or person to Facebook, and its User Operations team investigates the report. If you’re getting warnings about things like spamming, chances are you just need to tweak how you’re using Facebook.
You can’t upload illegal content to Facebook
Facebook users live in virtually every country in the world, so Facebook is often obligated to respect the local laws for its users. Respecting these laws is something Facebook has to do regardless of its own position on pornography (where minors can see it), copyrighted material, hate speech, depictions of crimes, and other offensive content.
However, doing so is also in line with Facebook’s value of being a safe, happy place for people 13 and older. Don’t confuse this with censorship; Facebook is all about freedom of speech and self-expression, but the moment that compromises anyone’s safety or breaks any law, disciplinary action is taken.