The internet can be loads of fun, and it's great to be able to play games and interact with your mates online.
But if you need to login to your fave site to enjoy it, be very careful you're not being conned.
Hackers have been taking advantage of children by building fake websites so they can steal your information and details. Adam's been investigating…
Emily from Liverpool loves Habbo Hotel. She told Newsround that a boy told her to use a special link he'd sent her to log into the game, and then she'd get free credits.
Adam and computer expert Chris Boyd
She did what he said, but she didn't get free credits. Instead she lost all the stuff she'd spent ages collecting.
Internet security expert Chris Boyd explained that hackers have been building fake Habbo websites so that they can steal stuff from players.
Scammers start by setting up a fake web page. They look EXACTLY like the real thing, apart from one tiny detail - the URL at the top of your browser won't be habbo.com or habbo.co.uk.
Like the real site, you login to get into your account, but instead of playing the game, your details are sent to the person who set up the site.
They can log into Habbo Hotel as you and then see all the personal information linked to your account.
Once in the game they can nick all your stuff, send rude messages to your mates, or do whatever they want. And it looks like you're doing it!
That's not the only fake site hackers are using to con people.
You may have been sent a link that promises free Xbox Live points or free games if you login through it.
But instead of getting free stuff, you're actually sending your login details to the person who created the site.
They can then login as you, and wreck your account. They could even steal real money from you if the account is linked to a parent's credit card, by copying the details from your account.
How to stop being hacked..
Computer expert Chris Boyd's tips on not being scammed online
The best advice is to be careful when online. There's nothing to be scared of as long as you think about what you're doing.
These aren't the only password scams around. If you use sites that you have to login to, be extra careful.
ALWAYS type in the URL of a site you want to visit. Don't use a random link to go to it, especially if someone has sent you that link promising free stuff.
And never enter your login details to anything other than the site you want to access. If you want to login to Xbox Live, only put your password into that site.
No proper company will EVER ask you to email them your login details, or create a brand new site that asks you to enter them. If it looks too good to be true, it probably is!
If you think you may have been scammed by something like this, get in touch with the company behind the site and they may be able to help.