Long Lived access token for facebook api
Long Lived access token for php sdk facebook applications
Facebook Access tokens are used to post or to retrieve information from facebook pages using applications in facebook.
Normally the access tokens are short lived and it will expire in an hour(60 minutes).
To get Long Lived access token for facebook application the following code can be used.
you will get long lived access token(for 60 days) and expiry time on executing the above code in browser.