Facebook has launched a Trusted Contacts security tool which allows users to name up to five friends who can help them access their account if it's been hacked or they've forgotten a password.

The social network first tested a Trusted Friends scheme back in October 2011 and not a huge amount seems to have changed judging by today's announcement.

Users who opt into the scheme can name three to five of their closest friends who'll all be sent a security code when they're unable to access the account.

Users will need three of the security codes in order to get back into their Facebook page, enabling them to choose a new password. The more friends you pick, the easier it should be to get back the information necessary to get back in.

Would you give this person a key?

In a post on its Notes page, Facebook advised users only to select those friends they'd be comfortable furnishing with a spare key to their house and those they're in contact with outside of Facebook.

"With trusted contacts," the company said, "there's no need to worry about remembering the answer to your security question or filling out long web forms to prove who you are. You can recover your account with help from your friends."

To set up trusted contacts, enter the settings section at Facebook.com.