title: how to create An app in twitter?
body: <p>I'm new in this ... I followed this steps </p>
  
  <p><a href="http://iag.me/socialmedia/how-to-create-a-twitter-app-in-8-easy-steps/" rel="nofollow">http://iag.me/socialmedia/how-to-create-a-twitter-app-in-8-easy-steps/</a></p>
  
  <p>but i don't know what's the exact URL i should write it ? i found different URLs on different examples .. but i don't have one ! </p>
  
  <p>and i read if i don't have URL yet i should put placeholder !! what's the placeholder ?</p>
  
  <p>and what's the callback URL </p>
  
  <p>i hope someone help me on this .</p>