Lay My Hat

Hi
Is a Doctype declaration necessary in the code of a website? If so:
1. What does it do?
2. How do I know what to put? I've looked on the www.w3.org site at the valid dtd list but haven't got a clue which one to use.
Thanks in advance
Canda

I think you would be safe to use HTML 4.01 Transitional.
It is probably the most common at the moment.
It just informs "whom it may concern" (the all important search engines) that you will obey by the rules of that standard.
And then - off course - you must stick to the rules.

janskov

Thanks for your help. I've used the doctype you suggested. Now I just have to sort out the error messages.

Canda