title: What is the difference between Ntxxx and ZWxxx?
body: <p>I tried to find the usage of NtqueryDirectoryFile() function.</p>
  
  <p><a href="http://msdn.microsoft.com/en-us/library/windows/hardware/ff556633%28v=vs.85%29.aspx" rel="nofollow">http://msdn.microsoft.com/en-us/library/windows/hardware/ff556633%28v=vs.85%29.aspx</a></p>
  
  <p>I refered the above link for this. But, They mentioned about Zwxxx (). I couldn't understand Ntxx and ZWxxx. Can anyone explain about this. </p>