W3C validation how impotant is it?

Plus are there degrees of error or is any error absolute?

[surfgatinho]

I've started trying to adhere to w3c html 4.01 transitional as much as I can. It does however seem to be a bit of a tall order. For example table cell background colours - I'm not giving these up!
And in CSS scrollbar attributes, I know they're pure IE but I like them.

My question is a) Is validation important for anything beyond browser compatibility and b) Does an error prevent parsing or is it just coped with and taken in th stride of things.

I am thinking more in terms of SE performance here than any higher virtuous position!

Thanks
Chris

[hartlandcat]

Table cell background colours: You are supposed to use CSS for this. Don't worry about 3.0 users.

As for coloured scrollbars... we had a long row about those in another forum, and we agreed that it's best to not use them. Why? Because, believe it or not, it means that some people can't find the scrollbar. Although people like us know that the scrollbar is always down the right hand side, seriously, not everyone does. Someone told me about how their colour blind mother nearly gave up on the internet because she was having dificulty seeing coloured scrollbars... then he directed her to Netscape 7.0. I personally hate coloured scrollbars -- no 3rd party should have the right to change any part my browsers theme.

As for coloured scrollbars being "pure IE", well that's not quite true. Coloured scrollbars will show up in IE 5.5+, Opera 7.0+ (if they've been enabled), Konqueror 3.0+, and possibly Safari and OmniWeb 4.5 (although I can't confirm the last two).

[hartlandcat]

Okay, so what you really wanted to know... W3C validation is important, but not important enough to have sleepless nights over because something you really need/want to use doesn't pass the validator. Table cell colours work in virtually all browsers released in the Summer of 1996 and later.

[jbinbpt]

Valdiation is really a good habit to get into. In my case, the WYSIWYG program I started out with wasn't configured properly for char set and doc type, but the pages were displaying ok. I didn't know the difference until I got a complaint.
You don't need to do everything, but run one through when you can.
Valdiate both HTML and CSS.