DOCTYPEs; one more time
If you’re sending your document as
text/html over the wire you should use a
DOCTYPE that triggers Standards Mode. I recommend
<!doctype html>. Otherwise, if you’re sending your document with the media type being
application/xml or ending with
+xml you can pick whatever
DOCTYPE you like. I recommend not having one at all. Otherwise, fix your media type.
This implies that whether or not your document will validate for a given
DOCTYPE doesn’t matter when picking one. This doesn’t mean
font elements or
target attributes are (always) ok to use. You should always strive for writing conforming documents. It means that if you have to use them you should not pick a
DOCTYPE that triggers a less than standards parsing and rendering mode in the browser.