Without consulting its users, the network began to showfacebook as e-mail accounts.

Facebook changed the default email account user to start showing social network. The move sparked the anger of his millions of “friends” who again are not taken into account when making changes to the platform.

The Facebook mail service was introduced in late 2010 and at that time the company called it the “future mail”.
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Long, the network tries to take ownership Hotmail and Gmail. The move is a new impulse to make Facebook the main communication channel surfers.

How the address is used
If someone wants to chat via Facebook Messenger, but can not access the network, for some reason, you can send text from another email account like Hotmail or Gmail with the email address of Facebook of the person you want to talk. The recipient will receive the message on the social network, and its answer will come to another account. So, you can have a conversion but through e-mail. It is a tool that would only be useful for those who are in contact through the social network and not have the staff e-mail address.

You can also send new emails to people from the Facebook page. In the “To” e-mail is written.

Changing the default mail
The e-mail Facebook appears by default on the profile of each user. But he can choose not to make it public. The only thing the user must do is enter information and edit contact information. There you can choose which mail account profile show.
Source: http://america.infobae.com