WCAG

Web Content Accessibility Guidelines (WCAG) is a group of documents that serve as regulations of how content is presented online. It is intended for web developers and authoring tool developers to follow the technical standards imposed on society. These guidelines aid and advocate people with disabilities to have access to content online The WCAG, published in May 1999, is considered one of the most important resources for making websites easily accessible. This initiative is often grouped with “Authoring Tool Accessibility Guidelines” and “User Agent Guidelines” as part of the World Wide Web Consortium’s Web Accessibility Initiative. In its organization, the WCAG 1.0 has 14 guidelines that Web authors are encourage to abide by. Under each guideline is a checklist organized by priority level, 1 having the most priority and 3 being of the least concern.
 * Guideline 1: Provide equivalent alternatives to auditory and visual content
 * Guideline 2: Don’t rely on colour alone
 * Guideline 3: Use markup and style sheets, and do so properly
 * Guideline 4: Clarify natural language usage
 * Guideline 5: Create tables that transform gracefully
 * Guideline 6: Ensure that pages featuring new technologies transform gracefully
 * Guideline 7: Ensure user control of time sensitive content changes
 * Guideline 8: Ensure direct accessibility of embedded user interfaces
 * Guideline 9: Design for device independence
 * Guideline 10: User interim solutions
 * Guideline 11: Use W3C technologies and guidelines
 * Guideline 12: Provide context and orientation information
 * Guideline 13: Provide clear navigation mechanisms
 * Guideline 14: Ensure that documents are clear and simple

WCAG 2.0
WCAG 2.0 was published on December 11th 2008. This new version consisted of twelve guidelines organized under four principles: perceivable, operable, understandable, and robust. Each guideline has specific testable success criteria.

Principles:
 * Perceivable (must be presentable to users in ways they can perceive)
 * Guideline 1.1: Provide text alternatives for any non-text content so that it can be changed into other forms people need, such as large print, braille, speech, symbols or simpler language.
 * Guideline 1.2: Time-based media: Provide alternatives for time-based media.
 * Guideline 1.3: Create content that can be presented in different ways (for example simpler layout) without losing information or structure.
 * Guideline 1.4: Make it easier for users to see and hear content including separating foreground from background.
 * Operable (User interface components and navigation must be operable)
 * Guideline 2.1: Make all functionality available from a keyboard.
 * Guideline 2.2: Provide users enough time to read and use content.
 * Guideline 2.3: Do not design content in a way that is known to cause seizures.
 * Guideline 2.4: Provide ways to help users navigate, find content, and determine where they are.
 * Understandable (Information and the operation of user interface must be understandable)
 * Guideline 3.1: Make text content readable and understandable.
 * Guideline 3.2: Make web pages appear and operate in predictable ways.
 * Guideline 3.3: Help users avoid and correct mistakes.
 * Robust (Content must be robust enough that it can be interpreted reliably by a wide variety of user agents, including assistive technologies)
 * Guideline 4.1.: Maximize compatibility with current and future user agents, including assistive technologies.