XHTML
The following example shows an HTML document and corresponding "XHTML" document, and the accompanying HTTP
Content-Type
headers they should be served with.
HTML document
<!-- Content-Type: text/html -->
<!
doctype
html
>
<
html
lang
=
"
en-US"
>
<
head
>
<
meta
charset
=
"
utf-8"
/>
<
title
>
HTML
</
title
>
</
head
>
<
body
>
<
p
>
I am a HTML document
</
p
>
</
body
>
</
html
>
XHTML document
<!-- Content-Type: application/xhtml+xml -->
<?xml version="1.0" encoding="UTF-8"?>
<
html
xmlns
=
"
http://www.w3.org/1999/xhtml"
xml:
lang
=
"
en-US"
>
<
head
>
<
title
>
XHTML
</
title
>
</
head
>
<
body
>
<
p
>
I am a XHTML document
</
p
>
</
body
>
</
html
>
In practice, very few "XHTML" documents are served over the web with a Content-Type: application/xhtml+xml
header. Instead, even though the documents are written to conform to XML syntax rules, they are served with a Content-Type: text/html
header — so browsers parse those documents using HTML parsers rather than XML parsers.