Readers beware. It looks like identity theft is rising and sites like Facebook and Twitter are the new "hunting ground" for criminals.
There were more than 148,000 victims in the UK in 2015, according to fraud prevention service Cifas.
That's up 57% in a year.
Researchers say personal details, often found on social media, are being used for taking out things like loans, credit cards or phone contracts in other people's names.
It can leave victims with big bills, or a bad credit rating (the points-based system lenders use to decide if you can borrow their cash).
The advice isn't to drastically change what you do online, but just think about it first and make sure your privacy settings are tight.
Here are some big things to avoid posting, to help keep your identity details to yourself...
Off on holiday? Lucky you. We're not jealous at all.
But if want to make your mates feel EVEN worse about being stuck in work by posting a snap of your passport - or if you fancy sharing that shocker of a mugshot - just don't do it on social media.
Your full name, your date of birth, your passport number... all things identity thieves would love to get their hands on.
A quick pic of your suitcase, your sunnies and your suntan lotion will work just as well for rubbing it in, but are simply useless to the fraudsters.
Your new pad
Woo hoo... you've got the keys. And who can resist posting that classic keyring shot?
Well, again, you might want to resist that temptation.
The chances of a random fraudster using a picture of your house to work out your new address might be slim.
But if they've already got enough other information about you, they might just get it. And there may be hidden clues like a street name lurking in the background.
Basically, don't post your current or previous address on social media if you can help it.
Your new car
So, you've got some nice new wheels. And a little bit more bragging might be in order, right?
That's fine, but just keep the registration number out of the shot.
The more unique details a fraudster can piece together about you, the more likely they'll be able to steal your precious identity.
Alright, we're not asking you to take your birthday off Facebook or Twitter, because let's face it, you'd feel pretty sad if no-one messaged you on your big day.
But just take the year off and that'll help protect you.
And you might be thankful as the birthdays keep coming too.
Your phone number
"Hey guys, dropped my phone down the toilet (again)! Here's my new number..."
We've all seen the posts. Or maybe you've added your number to your info on social media. If so, you might want to think about deleting it.
Not only can fraudsters potentially use the number to try to "prove" they are you - they might also want to give you a call.
With some of the other info they've managed to piece together, they may convince you they're your bank (for example) and trick you into handing over even more details, like passwords.
Your National Insurance number
Whether you've turned 16 and you've got your National Insurance number, or you feel like a bit of bragging again with a picture of your payslip after a nice little pay rise... don't make life easy for the fraudsters.
This number's unique to you, so best to keep to just keep it to yourself and anyone official who needs it, like your boss.
Alright, this is pretty obvious. We all know not to put our passwords on social media, don't we?
But it's also about choosing your passwords really carefully.
If you're officially "in a relationship", or tagged in pictures with boyfriends, girlfriends, best not to use their names for login details or security questions.
Likewise, if your favourite sports team, actor or band is obvious online, don't use that.
Your bank details
Again, this one may sound obvious. But some have been known to get a little excited about their snazzy new bank cards, and tweeted pictures of them. Doh!
Don't publicly share your card or account numbers on social media UNDER ANY CIRCUMSTANCES.
And best to not even let on who you bank with, like by publicly complaining about the service.
Seriously, just don't make it easy for them.
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