title: PHP: I can't have users logged into site on multiple browsers
body: <p>Apologies if this question is already posted.  I didn't find the answer i was looking for when searching through the related questions.</p>
  
  <p>I have a login system I've just created that works with Facebook. Once the user logs in with their Facebook info and then I create profile in my database for them. I start a session upon successful login and store the user's id in that session. This setup so far has worked fine, but I've recently noticed if I try to login to the site on another browser (1xChrome, 1xIE, so on...) at the same time it wont let me.  How can I fix this problem?  I would like the user to be able to not only log into multiple browsers on the same computer at the same time, but if they stay logged in at home be able to still log in from another computer.</p>
  
  <p>Any help is greatly appreciated!</p>
  
  <p>Thanks! </p>
  
  <p><strong>EDIT:</strong> Yes I'm interested in allowing user's to log into multiple browsers as in 1xChrome, 1xIE, 1xSafari, etc.  I should've been more clear. sorry.</p>