Non-replaced vs. replaced element

replaced Element

以 MDN 为准:

In CSS, a replaced element is an element whose representation is outside the scope of CSS. These are a type of external object whose representation is independent of the CSS. Typical replaced elements are <img>, <object>, <video> or form elements like <textarea> and <input>. Some elements, like <audio> or <canvas> are replaced elements only in specific cases. Objects inserted using the CSS content properties are anonymous replaced elements.

CSS handles replaced elements specifically in some cases, like when calculating margins and some auto values.
Note that some replaced elements, but not all, have intrinsic dimensions or a defined baseline, which is used by some CSS properties like vertical-align.

CSS 里,可替换元素(replaced element)的展现不是由CSS来控制的。这些元素是一类 外观渲染独立于CSS的 外部对象。 典型的可替换元素有 <img>、 <object>、 <video> 和 表单元素,如<textarea>、 <input>。 某些元素只在一些特殊情况下表现为可替换元素,例如<audio> 和 <canvas>。 通过 CSS content 属性来插入的对象 被称作 匿名可替换元素(anonymous replaced elements)。