One: Lists are very ordered lists; unordered lists; custom lists.
Ordered List: An ordered list starts with the <ol> tag. Each list item starts with a <li> tag.
Unordered list: The unordered list starts with the <ul> tag. Each list item starts with <li>.
Custom lists: Custom lists start with a <dl> tag. Each custom list item begins with <dt>. The definition of each custom list item begins with <dd>.
List items can use paragraphs, line breaks, pictures, links, other lists, etc.
| <ol> | Define an ordered list. |
| <ul> | Define an unordered list. |
| <li> | Define list items. |
| <dl> | Define the definition list. |
| <dt> | Define the definition item. |
| <dd> | Define the description of the definition. |
Two: element block
div: The div element is a block-level element, which is a container that can be used to group other HTML elements.
The div element has no specific meaning. In addition, since it is a block-level element, browsers display line breaks before and after it. Another common use is document layout.
Another common use is document layout.
span: The span element is an inline element that can be used as a container for text.
The span element also has no specific meaning
| <div> | Defines a division or section (division/section) in the document. |
| <span> | Defines a span, which is used to combine inline elements in a document. |
Frame label (Frame)
Frame 标签定义了放置在每个框架中的 HTML 文档。
- 框架结构标签（<frameset>）定义如何将窗口分割为框架
- 每个 frameset 定义了一系列行或列
- rows/columns 的值规定了每行或每列占据屏幕的面积
注意事项：
假如一个框架有可见边框，用户可以拖动边框来改变它的大小。为了避免这种情况发生，可以在 <frame> 标签中加入：noresize="noresize"。 不支持框架的浏览器添加 <noframes> 标签。
提示：不能将 <body></body> 标签与 <frameset></frameset> 标签同时使用！不过，假如你添加包含一段文本的 <noframes> 标签，就必须将这段文字嵌套于 <body></body> 标签内。
类表例子：
<html>
<body>
<h2>一个定义列表：</h2>
<dl>
<dt>计算机</dt>
<dd>用来计算的仪器 ... ...</dd>
<dt>显示器</dt>
<dd>以视觉方式显示信息的装置 ... ...</dd>
</dl>
</body>
</html>