title: jquery how to check if browser tab/window the selected is on our page?
body: <p>How do check if a the user has the browser's tab/window currently on our page</p>
  
  <pre><code>function userisonourpage()
  {
  //do something
  }
  </code></pre>
  
  <p>And when a user switches the tab/window to our page ?</p>
  
  <pre><code>function tabswitched()
  {
  //dom something here too
  }
  </code></pre>
  
  <p>Just like in many places u switch to the page and the title changes i know the title can be changed with : <code>document.title</code>
  but dont know how to implement those functions.</p>
  
  <p>Thanks :D</p>