In general terms, when we say that a website is accessible, we mean that the content of the site is available, and its functionality can be operated, literally, by anyone. If we wrongly assume that all users can see and use a mouse, a keyboard, or even a touchscreen, interacting with page content the same way we do, we will be led to an experience that works well for some people, but creates problems ranging from simple hassles to unpassable obstacles to others.
Accessibility, then, refers to the experience of users who may be outside the narrow typical user bandwidth, who can access or interact with things differently than expected. Specifically, it refers to users experiencing some kind of disability—and ...