<small>：备注元素

<p>
  MDN Web Docs is a learning platform for Web technologies and the software that
  powers the Web.
</p>

<hr />

<p>
  <small
    >The content is licensed under a Creative Commons Attribution-ShareAlike 2.5
    Generic License.</small
  >
</p>

small {
  font-size: 0.7em;
}

<p>
  这是第一句。
  <small>整个句子采用了较小的字体显示。</small>
</p>

<p>
  这是第一句。
  <span style="font-size:0.8em">整个句子采用了较小的字体显示。</span>
</p>