Operable

It's important to provide consistent navigation regions to navigate between a site's pages and—where there is a lot content on each page—between sections of pages.

Autocomplete widgets can be helpful for accessibility because they can make it easier to enter text by providing suggestions based on the characters initially typed.

For a number of reasons including data persistence, performance and security, it is sometimes beneficial to terminate idle user sessions. It's important to warn people a session is about to expire and give them the option to continue.

Modal dialogs can enhance usability by focusing attention on a specific message that requires a user action to continue.

An accessible modal dialog is one where keyboard focus is managed properly, and the correct information is exposed to screen readers.

Expandables (sometimes called “collapsible” or “disclosure widgets”) are simple interface patterns that allow you to expand and collapse content.

Interactive elements should not be difficult to select or activate when using a mouse or a touchscreen.

Generous sizing and spacing is important, and their implied visual “hit area” should correspond to the control’s active area.

Interactive elements should, under most circumstances, be focusable in the order that they appear in the source code. This helps people who are using the keyboard or alternative input devices to follow focus in a logical order.

All interactive elements should indicate when they’re focused so that users know which element they are currently interacting with. This is where focus styles come into play.

Sometimes, design requirements mean that you need to create a custom interactive element rather than using a native HTML element.

Your element will not be accessible by keyboard unless it is included in focus order and it can be activated using keys.

If an active element is intended to be unavailable in a particular state and it’s hidden from view, it should not be able to receive focus.