Who accessibility is for

Accessibility means people can perceive, understand, navigate and interact with your site regardless of disability. That includes people who are blind or have low vision, people who are deaf or hard of hearing, people with motor impairments who use a keyboard, switch or voice control, and people with cognitive or learning disabilities.

It also includes situations that are not disabilities at all. Someone holding a baby uses one hand. Someone on a train cannot play audio. Someone with a migraine wants less motion. Designing for permanent disabilities usually improves the experience for these situational cases too.

How people actually use the web

• Screen reader users hear the page read aloud and move through it by headings, links, landmarks and form fields. Many never listen to a page top to bottom. They jump.
• Keyboard users move with Tab, Shift+Tab, arrow keys, Enter and Space. If something only works with a mouse, it does not work for them.
• Screen magnifier users see a small part of the page at a time, so content placed far from its label is easy to miss.
• Voice control users say the visible name of a control, so a button labelled "Submit" in text but named something else in code will not respond.

What WCAG is

The Web Content Accessibility Guidelines are published by the W3C. Version 2.2, released in October 2023, is the current recommendation and is backwards compatible with 2.1. Success criteria come in three levels: A, AA and AAA. Most laws and policies point to level AA, and that is our target in this course.

WCAG is organised under four principles, often remembered as POUR: perceivable, operable, understandable and robust. You do not need to learn every criterion by number. If you understand the principles and the common failures, you will catch most issues while building.

The demo site

Download the course starter. It is a small event booking page with nine deliberate accessibility problems. Do not fix anything yet. In the next lessons we will try it with a keyboard and a screen reader first, so you experience the problems before you solve them.