将这四个概念联系在一起,是因为它们是我们创建运营商业网站必须考虑四个相辅相成的四个方面: 可以这样说，平衡Usability（可用性）和Accessibility（可访问性），优化达到Approachability（可到达性或搜索引擎友好性），最终实现Profitability（盈利能力）。
Usability Resources （可用性参考资料）
The views and opinions presented in these papers, articles and opinion pieces are those of the author as an individual and may not be representative of the Association of Accessibility Professionals as a whole.
Best practice:
Beware of Opening Links in a New Window
Ten Ways to Speed up the Download Time of Your Web Pages
Opinion pieces
The Right Time to Spend Your Usability Budget
The Secret Benefit of Search Engine Optimisation: Increased Usability
Ten Usability Blunders of the Big Players
Accessibility Resources（可访问性参考资料）
The views and opinions presented in these papers, articles and opinion pieces are those of the author as an individual and may not be representative of the Association of Accessibility Professionals as a whole.
Introduction to Web Accessibility
Disability Discrimination Act (DDA) & Web Accessibility
Ten Quick Tests to Check Your Website for Accessibility
How Disabled Users Access the Internet
How People With Impairments Use the Internet
Accessibility: On a Shoe-String
Web Content Accessibility Guidelines in brief
Accessibility Benefits
Benefits of an Accessible Website - Part 1: Increase in Reach
Benefits of an Accessible Website - Part 2: The Business Case
Functional, Accessible and Good-Looking
The Secret Benefit of Accessibility Part 1: Increased Usability
The Secret Benefit of Accessibility Part 2: A Higher Search Engine Ranking
Accessibility: Not Such a Bitter Pill
Opinion Pieces
Access Keys, of Limited Practical Value
Ten Accessibility Blunders of the Big Players
Manchester United: Top of the Web Accessibility League?
Is Accessibility the Last Great Alchemy?
Accessibility: Panning for Gold
Practical solutions for web developers
