Understanding the diversity of users
In summary, accessibility is really about making sure that the content and the website we create is usable to people with various impairments or abilities.
Some statistics on disability for the US:
- Around 2% of the population has some kind of vision disability (i.e. are blind or have significant difficulty seeing even with glasses)
- Around 50% of the population has some kind of clinically significant refractive error (a visual impairment which may be corrected with glasses if mild enough)
- Around 8% of males and 0.5% of females have some form of color vision deficiency
- Around 2% of adults have a hearing disability
- Over 4% have a cognitive disability (difficulty remembering, concentrating, or making decisions)
Sources: