<!doctype> vs <!DOCTYPE>

[CHunt]

I'm trying to switch to xhtml 1.0 using Frontpage 2002 as an editor. When I type <!DOCTYPE ....etc> Frontpage changes it back to <!doctype...etc> . Does it make any difference when the browsers read the page? Are they the same?

Thanks

[Twey]

Don't go to XHTML just yet -- IE still doesn't support it. Stick with HTML 4.01 Strict.

SGML (and thus HTML) is case insensitive: it doesn't care if you write <!DOCTYPE>, <!doctype>, or <!DoCtYpE>. XML, however (and thus XHTML) is case sensitive, and only <!DOCTYPE> is acceptable, I believe.

[djr33]

To expand a bit--
With html (not xml) cases don't matter, but there are standards for clarity.
UPPERCASE for machine written code and lowercase for human-written code.
It's not something that you must stick to, but perhaps helpful in some cases.
Not a bad idea to know what changes you made yourself (ie, what's lowercase code).