title: What {% %} and {{ }} mean in HTML?
body: <p>I have recently started to learn Django, so I came across with some HTML templates, but those are pretty unfamiliar for me, they mostly consist of {% and {{</p>
  <p>For example:</p>
  <pre><code>&lt;h1&gt;{{ question.question_text }}&lt;/h1&gt;
  
  &lt;ul&gt;
  {% for choice in question.choice_set.all %}
      &lt;li&gt;{{ choice.choice_text }} -- {{ choice.votes }} vote{{ choice.votes|pluralize }}&lt;/li&gt;
  {% endfor %}
  &lt;/ul&gt;
  
  &lt;a href=&quot;{% url 'polls:detail' question.id %}&quot;&gt;Vote again?&lt;/a&gt;
  </code></pre>
  <p>What are they? Implementations from other languages or HTML syntax? I'd be happy to get some docs, websites or examples too.</p>