I want to create a "**Login through Facebook**" on a website using Graph API like Stack Overflow does.

Once you login to StackOverflow through Facebook for the first time ( If you have an account in Stack Overflow using the email address same as the Facebook email, stack overflow will log you in to that account ) it will create an account for you in stack overflow automatically. This process extracts email address and full name from your facebook account and stores it in its database. 

My question is **Does Facebook data storage policy allow this?**

<http://developers.facebook.com/policy/#data>