The BBC published an official social media guide Thursday, codifying the "don't do anything stupid" rule media organizations generally hope their employees will follow. As we all know, free-wheeling tweeting and tumbling can get you into serious trouble. And, given that some news folk learned the ropes on their Remingtons, it's not a bad idea for media companies to set guidelines for their employees.

This isn't the first news organization to issue official rules to its journalists. The Associated Press, LA Times, and NPR are just a few others who've taken the precaution to avoid any snafus. Perusing the handbooks of these esteemed media companies, you'll find common messages--important lessons for anyone with a computer.

The Internet isn't private. All social media guides emphasize that privacy does not exist online. If you do something shady online, people will find out. The BBC reminds its people, "you are on show to your friends and anyone else who sees what you write, as a representative of the BBC. If you are editorial staff, it doesn't make much difference whether or not you identify yourself as someone who works for the BBC."

Online chatter is not like telling a secret in person, explains the LA Times, "It’s not just like uttering a comment over a beer with your friends: It's all too easy for someone to copy material out of restricted pages and redirect it elsewhere for wider viewing."

Privacy settings don't really work, "Even if you use privacy tools (determining who can view your page or profile, for instance), assume that everything you write, exchange or receive on a social media site is public," warns NPR.

Don't be an idiot. The BBC handbook spells it out, "as a BBC member of staff--and especially as someone who works in News --there are particular considerations to bear in mind. They can all be summarised as: 'Don't do anything stupid'." Act like a better version of yourself online, anything marginally silly you do will be used against you.

Of course, you don't have to give up your entire personality. "Sometimes AP staffers ask if they’re free to comment in social media on matters like sports and entertainment. The answer is yes, with a couple of reasonable exceptions," the Associated Press explains. "First, trash-talking about anyone (or team or company or celebrity) reflects badly on staffers and the AP." Don't brawl on the Internet. Just don't.

Never forget: The Internet is seductive. The BBC bestows a nugget of very useful advice, "Don't be seduced by the informality of social media into bringing the BBC into disrepute." Updating Facebook, Twitter, Tumblr, etc. is all too easy. Think before you Tweet.