With PHP, CSS, Ruby On Rails and so on, it's easy to forget that HTML is where it all began. Even with its age, HTML is still essential for every wanna-be web developer, so we've gathered 30+ resources for you to learn, code, validate and more.
Character Guides
Character Reference - Lists 252 usable characters in HTML and shows you their coding via mouse rollover.
HTMLPlayground.com - Click on a tag, get an explanation of what it does, how to write the code and how it would appear on a page.
Special Characters - A chart for just about every character in HTML and the codes to use them, along with a description of each.
W3Schools.com - Offers lots of tutorials, but this page specifically gives you a basic description of the majority of the tags.
Webmonkey.com - A great site for general HTML tips, but this page specifically teaches you the special characters such as ♥.
Tools
Alleycode.com - An HTML editor with a built-in tutorial for beginners, and some features for advanced users.
Amaya - An open source project building a web editor that currently runs on Windows, Mac OS X, and Linux.
Aptana - An open source editor that will edit HTML, CSS, create AJAX apps, do Ruby On Rails, and more.
Bluefish - An open source HTML editor that runs on systems such as Linux, FreeBSD, Mac OS X and more.
Coffee Cup HTML Editor - A drag and drop HTML editor with built-in FTP support.
HTMLKit.com - A free editor for HTML, XHTML, XML, CSS; it includes Tidy HTML to make sure your code stays clean.
PageBreeze.com - A free HTML editor with both code and WYSIWYG modes, drag-and-drop, and more.
Pingdom Tools - Enter your site address and get a visual representation of how long each item took to load.
Test Everything - Provides numerous tools to check every aspect of your site, including code validators.
TextFixer.com - Includes tools to capitalize sentences, convert text to HTML, convert line breaks and more.
TheJackolsDen.com - Offers lots of tips on various aspects of site building, but this cheatsheet specifically talks about your htaccess file which can control who, or what, accesses your files.
Tutorials
Bare Bones Guide to HTML - A basic guide to everything you need to know about HTML.
EchoEcho.com - Numerous HTML tutorials including how to do background images, form fields, add passwords and more.
HTML.net - 15 lessons in HTML for free, also comes in multiple languages.
HTMLBasix.com - Features HTML tools for beginners to advanced web masters.
HTMLCodeTutorial.com - Tutorials for all aspects of HTML coding, and active forums for troubleshooting help.
HTMLDog.com - Has beginner, intermediate, and advanced tutorials for HTML and CSS.
HTMLGoodies.com - Tutorials on just about every aspect of HTML you can think of, with lots of visual examples.
HTMLTutorials.ca - 21 free lessons to get you started with learning HTML.
PageTutor.com - Has lessons for all sorts of HTML tricks such as making tables and frames.
YourHTMLSource.com - Contains all sorts of HTML tutorials, lessons on web-safe colors and more.
Validators
AlwaysValid.com - Will automatically check your HTML once a week on your site and mail you the results telling you what doesn't work.
AnyBrowser.com - Offers a lot of tools for testing your site in different browsers, including an HTML validator.
Tidy HTML - Validates and cleans up your code.
W3C Markup Validator - Enter your webpage's address, upload a file, or use direct input to validate your HTML.
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