HTML links

HTML, it’s at the root of all web pages, you cannot be a good web designer without knowing HTML

A List Apart
Great online magazine for learning all kinds of web design techniques.
XHTML: The Definitive Guide
This is a good place to get started, and also something that you will be able to go back to throughout the years as you have questions
Validate Your Site
Validates your entire site (up to 100 pages anyway). You can also target directories to get the rest if you have over 100 pages.
XHTML Character Entities
By far the best reference for Character Entities
HTML Email Design
Some advice for HTML emails
24 Ways
Similar to this page, 24 Ways is a collection of links to other tutorials.
Vitamin
A online magazine for learning front end development techniques.
HTML Form Security
Techniques for improving the security of web forms
More HTML Form Security
Techniques for improving the security of web forms
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