title: What's the `x_budle-g2-g1.crt` in Apache certificate directory?
body: <p>I applied the Apache certificates from Goddady, in the directory there have:</p>
  
  <p><a href="https://i.stack.imgur.com/gb1lr.png" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/gb1lr.png" alt="enter image description here"></a></p>
  
  <p>I checked them, the <code>x.crt</code> content is as the same as <code>x.pem</code>(only one <code>CERTIFICATE</code>), the <code>x_bundle-g2-g1.crt</code> has 3 <code>CERTIFICATE</code> in it.</p>
  
  <p>Why there need the same content <code>x.crt</code> and <code>x.pem</code>?<br>
  What's the function of <code>x_bundle-g2-g1.crt</code>, where there have 3 <code>CERTIFICATE</code>, whether them refer to <code>x_bundle</code>, <code>g2</code> and <code>g1</code>?</p>