title: How to remove the lines which appear on file B from another file A?
body: <p>I have a large <strong>file A</strong> (consisting of emails), one line for each mail. I also have another <strong>file B</strong> that contains another set of mails.</p>
  
  <p>Which command would I use to remove all the addresses that appear in file B from the file A.</p>
  
  <p>So, if file A contained:</p>
  
  <pre><code>A
  B
  C
  </code></pre>
  
  <p>and file B contained:</p>
  
  <pre><code>B    
  D
  E
  </code></pre>
  
  <p>Then file A should be left with:</p>
  
  <pre><code>A
  C
  </code></pre>
  
  <p>Now I know this is a question that might have been asked more often, but I only found <a href="http://www.thelinuxblog.com/remove-lines-that-are-in-another-file/" rel="noreferrer">one command online</a> that gave me an error with a bad delimiter.</p>
  
  <p>Any help would be much appreciated! Somebody will surely come up with a clever one-liner, but I'm not the shell expert.</p>