Accessibility generally means equal or equivalent access by a person with a disability. Technology is accessible if it can be used as effectively by people with disabilities as by those without. However, this doesn’t mean that, for example, a blind user will complete a task on a website as quickly as one who can see. (Listening takes longer than looking at the screen and reading.) But it does mean that if a blind parent visits your school district’s website they will get the same information as a person who can see. The same is true of other approaches to making tech accessible.
