title: What does it mean !{0}, !{1}, !{2} ... on zsh in Ubuntu?
body: <p>Recently, I accidentally typed <code>!{0}</code>. I think it is some kind of special zsh function because it showed one of my previous commands while I execute it.</p>
  
  <p>What does it mean on zsh?</p>
  
  <pre><code>$ !{0}
  </code></pre>
  
  <p>Note: I'm using zsh on Ubuntu.</p>