title: msdn: What is "Thread Safety"?
body: <p>In many MSDN documents, this is written under the Thread Safety heading;</p>
  
  <p>"Any public static  (Shared  in Visual Basic) members of this type are thread safe. Any instance members are not guaranteed to be thread safe."</p>
  
  <p>for example; <a href="http://msdn.microsoft.com/en-us/library/system.net.sockets.socketasynceventargs.aspx" rel="noreferrer">here</a></p>
  
  <p>can someone explain it please in a rather simple way?
  Thank you :)</p>