Facebook security is a big topic. Here we point out the most important steps to take. Facebook Privacy Settings are explained on a separate page here.
Change your Facebook Security Settings from default NOW
By default Facebook is inherently insecure since you browse it in clear http instead of encrypted https. This means that if you browse Facebook from a public hotspot a hacker at the same public hotspot can easily get your Facebook account. The same is true if you access Facebook from a network not completely under your control.
So the first step is to go to your Account Settings and click on the gold Security Shield button on the left hand side. This will bring you to your account settings page.
The first thing to do is to enable secure browsing. This will enable browsing in encrypted https on devices that support it. This includes your computer but does not include your smartphone. To secure your smartphone and perform the next two steps.
Enable Login Notifications. Now if your account is used from a device that you have not used before you will be notified by email or text message. Facebook currently cannot send text messages to Google voice numbers or for phone numbers for which you have enabled Google Voice mail.
Enable login approvals. This will require you to enter an approval code every time you access Facebook from a new device. Facebook will send you the approval code. This will guard against hackers gaining access to your account and trying to login.
Do not use your full birth date on your profile.
Never give out your cell phone number to strangers or enter it into an app. Rogue applications can use your cell phone number to place charges on your cell phone account.
Do not mention on Facebook that you will be away from home.
Control physical access to your computer and mobile phone.
Since all your friends have access to your personal data your security depends on the weakest link in your network. If one of your friends behaves irresponsibly by clicking on obvious scam app links or engaging in other questionable behavior, your security may be at risk. Your choices are educating your friend on safe behavior or unfriending him or her.
Only be Facebook friends with people you know.
Here is Facebook's own Facebook Security Guide.
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