title: Explain "Leader/Follower" Pattern
body: <p>I can't seem to find a good and accessible explanation of "Leader/Follower" pattern. All explanations are simply completely meaningless as in <a href="https://www.dre.vanderbilt.edu/~schmidt/POSA/POSA2/conc-patterns.html" rel="nofollow noreferrer">1</a>.</p>
  
  <p>Can anyone explain to the <em>the mechanics</em> of how this pattern works, and why and how it improves performance over more traditional asynchronous IO models? Examples and links to diagrams are appreciated too.</p>