title: What is the difference between systemd's 'oneshot' and 'simple' service types?
body: <p>What is the difference between <code>systemd</code> service <code>Type</code> <code>oneshot</code> and <code>simple</code>? 
  This <a href="https://jason.the-graham.com/2013/03/06/how-to-use-systemd-timers/" rel="noreferrer" title="link">link</a> states to use <code>simple</code> instead of <code>oneshot</code> for timers.  I am not able to understand it correctly.</p>