title: what is {% block content %} and {% endblock content %} for in Django?
body: <p>so I just started reading a book on Django (for beginners) and I came across the following code snipet:</p>
  
  <pre><code>&lt;header&gt;
  
  &lt;a href="{% url 'home' %}"&gt;Home&lt;/a&gt; | &lt;a href="{% url 'about' %}"&gt;About&lt;/a&gt;
  
  &lt;/header&gt;
  
  {% block content %}
  {% endblock content %}
  </code></pre>
  
  <p>Could anyone possibly explain to me what is the use of <code>{% block content %}</code> and <code>{% endblock content %}</code>? Thank you very much in advance!</p>