And to highlight the really important parts of this article:
". . . preventative tips for those who want to take the security of their online profile into their own hands:
• Be suspicious of anyone -- even friends -- who ask for money over the Internet. Verify their circumstances independently, either by calling them directly, or checking with mutual friends.
• Choose a strong password and use unique credentials for each of your Web accounts. Facebook says hackers tap into one site and then try to reuse passwords on others.
• Use an up-to-date browser that features an anti-phishing blacklist.
• Use and run anti-virus software on your computer.
• Reset your Facebook password if you suspect your account has been compromised.
• Have more than one contact e-mail address. This will help if one of them is hacked.
Source: CNN"
Or, as your mom always says... never talk to strangers!