HTML links

General

World Wide Web Consortium ("W3C") http://www.w3.org/
The standards forum for the Web
Jakob Nielsen's Alertbox http://www.useit.com/alertbox/
A "Column on Web Usability." This is far and away the best online resource on Web design I've yet discovered. It caused me to change the basic design of this Web site back to no-frames after a year of various frames designs.
Xenu logo (11K)Xenu's Link Sleuth http://home.snafu.de/tilman/xenulink.html
Amazing free link tester uses preemptive multithreading to test sites super fast. You can investigate broken links while referring directly to the program's simple spreadsheet-like display. Xenu's Link Sleuth is free software but not open source.
CyberSpyder http://www.cyberspyder.com/
Another link tester
Open Directory list of link testers http://dmoz.org/Computers/Software/Internet/Site_Management/Link_Management/
See the link tester section of my Web publishing page for more discussion.
HTML Tidy home page http://tidy.sourceforge.net/
HTML Tidy project page http://sourceforge.net/projects/tidy
HTML Tidy original home page http://www.w3.org/People/Raggett/tidy/
Sophisticated cross-platform command-line utility, useful for cleaning up presentational HTML code in favor of structural HTML. It can also remove the unwanted dreck from HTML files created by Microsoft Word, and convert ordinary HTML to rigorous XHTML. There are links on the SourceForge homepage to some GUI-interface text editors that use the HTML Tidy library, but I haven't had good luck with the the ones I've tried so far.
Notepad++ home page http://notepad-plus.sourceforge.net/
Notepad++ project page http://sourceforge.net/projects/notepad-plus/
An open-source full service text editor (not linked on the Sourceforge Tidy page) that uses the HTML Tidy library; configurable syntax highlighting, multi-document and multi-view interface, bookmarks, search and replace, including in open documents and in files and with regular expressions support.
TidyGUI http://perso.orange.fr/ablavier/TidyGUI/
A user-friendly graphical Windows front-end for HTML Tidy that seems to work well enough, including converting HTML to XHTML. Identified as a Tidy Classic product, based on a 4 Aug 2000 version of HTML Tidy and no longer maintained. For the current HTML Tidy mods you'll need to get the command-line utility linked above.
FreeFind http://www.freefind.com/
Free advertising-supported keyword site search that can be added to anybody's Web site
W3C HTML validator http://validator.w3.org/
Web Design Group HTML validator http://www.htmlhelp.com/tools/validator/
These two HTML validators seem to flag the same code on the same pages, but the W3C one gives you additional information about typical causes of different error types.
Resources for Creating Web Sites http://wp.netscape.com/browsers/createsites/
HTML tutorial http://www.dynamicdeezign.com/html/
Web Pages That Suck http://www.webpagesthatsuck.com/
"Learn good Web design by looking at bad Web design" (and hope you don't find your own site featured!)

Browsers

Mozilla Firefox http://www.mozilla.com/firefox/
Superior free Web browser from the open-source community. Popup blocking, tabbed browsing.
SeaMonkey http://www.mozilla.org/projects/seamonkey/
The current incarnation of the integrated Internet suite that used to be called Mozilla Suite, which was deemphasized at Mozilla in early 2005 in favor of development of the standalone Firefox and Thunderbird clients.
Opera http://www.opera.com/
You may never have heard of it, but Opera was the first browser with good CSS support, and downloads faster and hogs less resources than other browsers. Popup blocking, tabbed browsing. Version 8.5+ is free with no ads or registration.
Opera Archives http://arc.opera.com/pub/opera/
Past Opera versions for download (ftp-style directory listings)
Opera version history and downloads http://www.markschenk.com/opera/history.html
Through Opera 7
Netscape Navigator homepage http://browser.netscape.com/
Now brought to you by the Netscape division of AOL, based on the latest Firefox release
Netscape Browser Archive http://sillydog.org/narchive/
Many past versions of Navigator/Communicator for all platforms
Microsoft Internet Explorer homepage http://www.microsoft.com/windows/ie/
Used by zillions of clueless corporate drones everywhere
WinPlanet Internet Explorer downloads http://cws.internet.com/category/2221-1-d.htm
Some links to download current and earlier MSIE versions. Be warned: MSIE generally will not tolerate other versions of itself on the same system; therefore I currently recommend Web-page testing using MSIE 6.
OldVersion.com http://www.oldversion.com/
This site also has past versions of Microsoft Internet Explorer, Mozilla Firefox, and Opera, including versions not now available from the home pages, plus superseded versions of 60+ other applications.
Safari http://www.apple.com/safari/
Camino http://www.caminobrowser.org/
Web browsers from Apple and Mozilla for Mac OS X only (Safari 3 beta now available for WinXP & Vista)
Amaya http://www.w3.org/Amaya/
W3C's test-bed Web browser & editor; available for Unix, 32-bit Windows, and some other platforms
NCSA Mosaic http://browsers.evolt.org/?mosaic-ncsa/
Mosaic 3.0 makes a good primitive browser representative for testing HTML; this archive has other common and obscure browsers as well.
Lynx http://lynx.browser.org/
Lynx http://lynx.isc.org/
A text-mode Web browser
Wikipedia: List of web browsers http://en.wikipedia.org/wiki/List_of_web_browsers
Wikipedia: Comparison of web browsers http://en.wikipedia.org/wiki/Comparison_of_web_browsers
Yahoo! Directory: Web browsers http://dir.yahoo.com/Computers_and_Internet/Software/Internet/World_Wide_Web/Browsers/

CSS

CSS Zen Garden: The Beauty in CSS Design http://www.csszengarden.com/
A stunning demonstration of the power and flexibility of modern CSS practice: contrasting treatments of one given unchanging HTML page by professional graphic designers, exclusively by means of different CSS stylesheets plus a few graphics.
Why tables for layout is stupid http://www.hotdesign.com/seybold/
A user-friendly, even management-friendly, Web presentation that lays out all the advantages of the efficient CSS+HTML style of Web design, relative to 1997-style presentational HTML with all layout controlled by borderless tables. (Not my link text: that's what they called it.)
CSS Cheat Sheet http://www.ilovejackdaniels.com/css/css-cheat-sheet/
Handy one-page guide to the nuts and bolts of CSS, which you can print out neatly from PDF format, in color if you want. I have mine in a plastic page-protector, with a list of HTML character entities facing the other way.
Eric Meyer's css/edge http://www.meyerweb.com/eric/css/edge/
Holy CSS, Zeldman! http://www.dezwozhere.com/links.html
Complete CSS Guide http://www.westciv.com/style_master/academy/css_tutorial/
CSS Layout Techniques http://www.glish.com/css/
CSS Crib Sheet http://www.mezzoblue.com/css/cribsheet/
List of important techniques (not a one-pager like the one above)
Guide to Cascading Style Sheets http://htmlhelp.com/reference/css/
W3C CSS page http://www.w3.org/Style/CSS/
Many good resources on CSS here
W3C Core Styles http://www.w3.org/StyleSheets/Core/
Some carefully-designed styles you can apply to your own pages, over the Internet, without even learning any CSS syntax
CSS tutorial http://www.dynamicdeezign.com/css/
W3C CSS validator http://jigsaw.w3.org/css-validator/
Web Design Group CSS validator http://www.htmlhelp.com/tools/csscheck/
This one seems to be a little stricter than the W3C one
comp.infosystems.www.authoring.stylesheets http://groups.google.com/group/comp.infosystems.www.authoring.stylesheets
Usenet newsgroup about CSS

JavaScript

JavaScript isn't for everybody, but if you've ever dabbled in programming it's not too hard. There are lots of "cookbook" sites where you can grab code widgets for free, modify them, and use them on your pages. (Some programmers like to condescendingly refer to this as "cargo-cult JavaScript." Ignore them.)

Danny Goodman's JavaScript Pages http://www.dannyg.com/examples/
Focus on JavaScript http://javascript.about.com/
The JavaScript Kit http://www.javascriptkit.com/
The JavaScript Source http://javascript.internet.com/
JavaScript Tutorial (W3Schools) http://www.w3schools.com/js/default.asp
JavaScript Workshop http://www.jsworkshop.com/
JavaScript.com http://www.javascript.com/
JavaScript and Web Site Usability http://www.webword.com/interviews/goodman.html
An interview with JavaScript guru and author Danny Goodman; somewhat dated but still makes lots of sense about what JavaScript is good for on the Web and how to use it well.
JavaScript home page http://www.mozilla.org/js/
comp.lang.javascript http://groups.google.com/group/comp.lang.javascript
Usenet newsgroup

Recommended books

If you're trying to do good Web content quickly, and you're going to use a WYSIWYG authorship tool, you don't need to learn everything there is to know about HTML tags, especially if you're going to use CSS for formatting. But it will help you understand what's going on, if you learn enough about the tags to understand generally how they nest and function. You might want a book for this purpose, or you may be able to learn enough from the many "HTML primer" Web sites, together with looking at the source code of simpler pages.

Sams Teach Yourself Web Publishing with HTML & XHTML in 21 Days [HTML primer] http://www.amazon.com/exec/obidos/ASIN/0672325195/
Fourth edition (May 2004) of a series of HTML "basics" books by Laura Lemay and others, that make an excellent Web-design and HTML primer.
Webmaster in a Nutshell [HTML & general primer] http://www.oreilly.com/catalog/webmaster2/
[Spainhour & Eckstein, ISBN 1565923251] This O'Reilly book is designed as a ready reference handbook for all primary Webmaster skill sets, but you can definitely use it as a primer for both HTML and CSS. You can order it at Amazon among other places. There are also brief sections on XML, JavaScript, CGI/Perl, PHP, and Web-server management.
Designing Web Usability [site design] http://www.useit.com/jakob/webusability/
[Jakob Nielsen, ISBN 156205810X] Home page for perhaps the best usability-focus Web-design book that has yet appeared. Here's an Amazon order link. You might also want to have a look at Dr. Nielsen's recommended books page. Internet World UK review (March 2000): "if the Web design company you are employing hasn't got a copy of this book on its shelves, you'll know to go somewhere else."
Cascading Style Sheets [CSS] http://www.informit.com/store/product.aspx?isbn=0321193121&rl=1
[3rd Ed. 2005 Håkon Wium Le & Bert Bos, ISBN 0321193121] The definitive reference on the CSS1 and CSS2 style-sheet specs, including lots of cool stuff not yet supported by any browser. Specific browser support is indicated with icons, for each property. Here's an order link at Amazon.
Cascading Style Sheets: The Definitive Guide http://www.oreilly.com/catalog/csstdg3/
3rd Ed., Eric Meyer, ISBN 0596527330
Designing Web Graphics.3 (3rd edition) Lynda Weinman, ISBN 1562059491
A guide to preparing bitmap graphics for the Web, including colors and dithering.

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