w3c是怎样规定标签的 到底有没有结束的斜杠?

哪种是更规范的写法

回复内容：

泻药
去查规范

HTML 4
The global structure of an HTML document
Start tag: required, End tag: forbidden


HTML5
4.2 Document metadata
Tag omission in text/html: No end tag.


所以：
第一种写法更贴近规范 这里有一个来自 * 的回答，它比较详细地解释了你这个问题：

html - Are self-closing tags valid in HTML5?

In HTML 5, means , the start tag. It is not a "self-closing tag". Instead, certain elements are designated as having no end tag, for example
. These are collectively called void elements. The slash is just syntactic sugar for people who are addicted to XML. Using the slash in a non-void element tag is invalid, but browsers parse it as the start tag anyway, leading to a mismatch in end tags.

自闭合标签使用html5的doctype时不用写反斜杠。