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CSS HTML Validator

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CSS HTML Validator Support

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W3C Links

HTML 5.3 Specification

HTML 5.2 Specification

HTML 5.1 Specification

HTML5 Specification (HTML 5.0)

HTML 4.01 Specification

XHTML™ 1.1 Recommendation

XHTML™ 1.0 Recommendation

Polyglot Markup: A robust profile of the HTML5 vocabulary

Cascading Style Sheets Level 2 Revision 1 (CSS 2.1) Specification

Accessibility Links

Web Content Accessibility Guidelines (WCAG) 2.0

Web Content Accessibility Guidelines 1.0


Section 508 Accessibility Links

Section 508 Website

Section 508 Standards

HTML Tidy Links

JavaScript Lint

JavaScript Lint Home

JavaScript Lint Documentation

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JSHint Home

JSHint Documentation


JSLint Home

JSLint Community

Nsgmls Links

SP by James Clark

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PHP Links

PHP Home

Windows PHP Downloads

Tutorial Links

Learning HTML and CSS (with links to HTML and CSS tutorials)