:check: content - the information in a Web page or Web application, including:
natural information such as text, images, and sounds
code or markup that defines structure, presentation, etc.
:check: Web browsers, media players, and other "user agents"
:check: assistive technology, in some cases - screen readers, alternative keyboards, switches, scanning software, etc
:check: users' knowledge, experiences, and in some cases, adaptive strategies using the Web
:check: developers - designers, coders, authors, etc., including developers with disabilities and users who contribute content
:check: authoring tools - software that creates Web sites, including blogs, content management systems, and learning management systems
:check: evaluation tools - Web accessibility evaluation tools, HTML validators, CSS validators, etc.