marquee and editing it

I have a client who wants to know if he can edit a marquee from his blind page (by typing in a text field) and this will update all the other pages on his site. He has no knowlege of HTML code to do this himself.

You could do this in a few ways. Either through incorporating a footer or header into the page that loads either through php if you want to get advance or basic (I think) xhtml and css commands.

That seems to be the eaisest way if you ask me. (but I'm not expert on web design)

You need a servers-side language to do that kind of thing.

You shouldn't use a marquee for accessibility reasons.

http://www.w3.org/TR/WAI-WEBCONTENT/#q33
http://www.google.com/search?q=accessibility+marquee

If you must have scrolling text, use JavaScript and provide a method to stop the scrolling.