title: copy content of a file
body: <p>When you do this:</p>
  
  <pre><code>cp file1 file2
  </code></pre>
  
  <p>(<code>file2</code> already exists)</p>
  
  <p>What actually happens behind the scene?</p>
  
  <p>1) Does the content of <code>file1</code> actually get copied to <code>file2</code>?</p>
  
  <p>2) Or is a new file created with the name <code>file2</code> (overriding the old one) which has same content of <code>file1</code>?</p>