title: Where viewstate value is stored on the client side in ASP.NET?
body: <p>An ASP.Net website that need to be accessed from C# code, but I don't understand the whole viewstate concept in details.</p>
  
  <p>There is a button that execute such a javascript onclick event <code>javascript:WebForm_DoPostBackWithOptions ...</code></p>
  
  <p>This makes POST request. One of the fields being posted is viewstate <code>&amp;__VIEWSTATE=</code></p>
  
  <p>Where it's value comes from, I can't seems to find complete and clear explanation?</p>