"The instruction here will “interpret” the W3C Web Content Accessibility Guidelines (WCAG 2.1), to make it easier to understand for a general audience. You will have an opportunity to experience barriers firsthand, then experience that content with the barriers removed, developing a practical understanding of web accessibility."
License: Creative Commons Attribution ShareAlike

The 10 most relevant guidelines are introduced. These guidelines should be foremost in your mind when auditing Web accessibility.

PAC ist ein kostenloses Tool der Stiftung „Zugang für alle“ zur Überprüfung der Barrierefreiheit von PDF-Dokumenten und -Formularen. Es unterstützt Experten und Betroffene bei der PDF/UA - Validierung.<<

"The extension generates a document-map or index of any web document structured with headings and/or with sections in HTML 5. It shows the headings structure, the errors in the structure (ie. incorrect levels), and it works as HTML5 Outliner too."

"The Web Developer extension adds various web developer tools to a browser. The extension is available for Chrome, Firefox and Opera, and will run on any platform that these browsers support including Windows, OS X and Linux."

"The vision behind the Accessibility Developer Guide is to bridge the gap between providers of websites and users with special needs." Here you get background, tools, examples.

"Web accessibility evaluation tools are software programs or online services that help you determine if web content meets accessibility guidelines. This page provides a list of evaluation tools that you can filter to find ones that match your particular needs."

This page links to resources to help evaluate web accessibility.
Content: Introduction, Initial Checks, Tools, Conformance Evaluation and Reports, People, Standards, Alternatives for Video Introduction - Resources Overview

WCAG Schnellreferenz so gefiltert, dass die Vorgaben angezeigt werden, die auch in der harmonisierten Norm der EU aufgeführt werden.

Wörterbuch-Wiki in Deutsch, Englisch, Spanisch, Italienisch und Ungarisch von Hep Hep Hurra e. V.. Der Verein unterstützt Vorhaben der Bildung mit Blick auf neue technische Enwicklungen, Barrierefreiheit, freie Information für alle und Gemeinschaftsarbeit.

"AChecker is a Web accessibility evalution tool" Prüft wahlweise gegen BITV 1.0, Section 508, Stanca Act, WCAG 1.0-A bis WCAG 2.0-AAA

"Tenon's tools, testing and training fix accessibility for your entire organisation."

"You can use the online WAVE tool by entering a web page address (URL). WAVE Firefox and Chrome extensions are available for testing accessibility directly within your web browser - handy for checking password protected, locally stored, or highly dynamic pages."

A customizable quick reference to Web Content Accessibility Guidelines (WCAG) 2 requirements (success criteria) and techniques.

Open Textbook Library: "Digital accessibility skills are in high demand, as the world becomes more aware of barriers in digital content that prevent some people from participating in a digital society. These are essential skills for web developers, and essential knowledge for organizations that want to ensure their web content is reaching the broadest audience possible."

Start building accessibility into your dev process today with a free axe extension or open source axe librarie. Integrate accessibility tools directly into development process, as with the Axe testing library Axe, which is now even included in the webhint extension for Microsoft Visual Studio. So when writing code, error msgs remind you if you forgot the attribute of an element.

Short Description of Laws and Principles.