title: How to mark text in gedit?
body: <p>Can anyone guide me how to mark text in my source code in gedit as shown below ("TODO" word was marked with yellow color)?</p>
  
  <p><img src="https://i.stack.imgur.com/SzdjD.png" alt="enter image description here"></p>
  
  <p>I can't find a feature in the editor for me to apply this highlighting (so it persists) to other parts of text, beyond what is automatically highlighted. Is this possible?</p>
  
  <p>I've <a href="http://www.mediafire.com/download/vi0t3fr53ievbpt/lab1b.c" rel="nofollow noreferrer">uploaded my source</a> (one small file) if you have gedit and want to view the highlighting to see what I'm trying to reproduce.</p>