Why do we not write slashes right before the closing[ > ] of some self closing tags?

Question

Some people say that every self closing tag should be written like this:
<img/>
But on solo learn, some tags like 'link' tag isn't written like <link/>
Does this create an error without a slash?

Answer 1

I'm pretty sure it is optional. I don't use the slash, and it has never thrown an error for me. 👍

Answer 2

Both ways are same and they don't create any error whether you choose to use a slash or not.

Answer 3

HTML5: the slash is optional.

HTML4: the slash is technically invalid. However, it's accepted by W3C's HTML validator.

XHTML: The slash is REQUIRED.