>tmp</code> might contain (the process is called "recursive"
          because, in order to remove <code>tmp</code>, we have to remove everything inside
          of <code>tmp</code>).</p>

        <blockquote>
          <p>As you've seen, some commands require arguments, like <code>mkdir</code>. Other
            commands do not require any arguments in order to work, like <code>ls</code>.
            In addition, most commands can also be given <strong>flags</strong>, like the <code>&#x2d;r</code>
       