title: What are WinMainCRTStartup, tmainCRTStartup, WinMain functions used for?
body: <blockquote>
    <p><strong>Possible Duplicates:</strong><br>
    <a href="https://stackoverflow.com/questions/4681443/apientry-twinmain-and-winapi-winmain-difference">&ldquo;APIENTRY _tWinMain&rdquo; and &ldquo;WINAPI WinMain&rdquo; difference</a><br>
    <a href="https://stackoverflow.com/questions/1583193/what-functions-does-winmaincrtstartup-perform">What functions does _WinMainCRTStartup perform?</a>  </p>
  </blockquote>
  
  
  
  <p>I just started to dive into windows programming. And when I tried to understand the win 32 program I noticed that the program has two entry points which are _tmainCRTStartup and _WinMainCRTStartup. Besides, I found the _tmainCRTStartup function also called _WinMain function. I just wonder what are they used for? And why there are two different entry points. </p>
  
  <p>Thanks!</p>