However, some tags do not need a closing tag. Examples are the line break tag (to force a line break) <br /> and the image tag <img src="photo URL" />. These tags do not need a closing tag, but they have a space followed by a backslash / at the end.
Now do meta tag need a closing tag? Or putting it another way, does meta tags occur in pairs? Look at this PDF book:
In HTML, Meta Tag definitions do not need to be closed with </ (Added by author of this blog: I believe when is meant by </ is a closing tag </any closing tag>), however you should not include any line breaks in your declaration of the Meta Tag as this can cause your web page to be incorrectly read by the search engine spider programs.
So what the author of that PDF book is saying is meta tags do not need a closing tag. However, please not that there is a difference between HTML and the newer XHTML (we should all try to follow XHTML now). In HTML the <meta> tag has no end tag. In XHTML the <meta> tag must be properly closed by putting a space followed by a backslash /, that is <meta />. Note that if there are other attributes after meta, the space and backslash must come after all the attributes and should be at the end of the tag.
<meta name="keywords" content="blog, blogger, blogging, blogger tips, blogger tricks, Blogger templates, Google Blogger" />
<meta name="description" content="Google Blogger tutorials and useful information, tips and tricks for bloggers" />
My take on tag without a corresponding closing tag in XHTML kind of close itself by add a space followed by a backslah / at the end of the tag.