 <code title="U+0030 DIGIT ZERO&#8211;U+0039 DIGIT NINE">0&#8211;9</code>,
      <code title="U+0061 LATIN SMALL LETTER A&#8211;U+007A LATIN SMALL LETTER Z">a&#8211;z</code>,
      and
      <code title="U+0041 LATIN CAPITAL LETTER A&#8211;U+005A LATIN CAPITAL LETTER Z">A&#8211;Z</code>.</li>
      <li>
      <dfn id="syntax-start-tags">start tags</dfn>
      consist of the following parts, in exactly the following
      order:
      <ol>
<li>A
        "<code title="U+003C LESS-THAN SIGN">&lt;</code>"
     