Basically, such an explanation must always have an historicalelement.
从根本上说,这样一种解释总是有某些历史因素。
2
Only by historical accident has the a element come to be the DE facto way to specify links.
只是由于历史的原因,a元素才变成了指定链接的实际方法。
3
For historical reasons, the XHTML specifications themselves go against this guideline when naming the root element HTML; it could just as well have been renamed to document.