WCAG in Plain English

All images and other non-text content (like icons, charts, audio, CAPTCHAs, or controls) must have a descriptive text alternative that conveys their meaning. Purely decorative content can be hidden from assistive technologies (e.g. using an empty alt attribute).

Visual information and relationships (like labels, headings, or groupings) must also be conveyed in the code using semantic HTML (e.g. <label for="">, <ul>, <h1>) or ARIA attributes (e.g. <aria-describedby>, <role="group">) so that assistive technologies can understand the structure.

Content must follow a logical and meaningful order in the code so it can be understood correctly by assistive technologies even if the visual layout differs.

Content must remain readable and usable in both portrait and landscape orientation, unless a specific one is essential (e.g. in a piano app that requires landscape to show the full keyboard).

The purpose of common form fields (like name, email, or address) must be defined in the code so that browsers and assistive technologies can offer input support, such as autocomplete.

The purpose of regions and common elements must be defined in the code using semantic HTML or ARIA attributes, so that; assistive technologies can communicate their meaning, and; browsers can adapt or simplify the interface (e.g. hide non-essential content).

If audio plays automatically for more than 3 seconds, it must be possible to pause the audio, stop the audio, or adjust the volume, without using system-wide controls.

Text must be actual text, not images of text (no exception, not even for design or aesthetic reasons).

Text remains readable and usable when spacing is changed using custom styles to at least 1.5× line height, 2× spacing after paragraphs, 0.12× letter spacing, 0.16× word spacing, without content being hidden, cut off, or broken.

When additional content appears on hover or keyboard focus (including long press on touch), it must stay visible until dismissed or no longer valid, be dismissible (e.g. using the key), and remain visible when hovered or focused.