Accessibility is about inclusion, ensuring that everyone has the ability to access, engage with, enjoy, or share an experience and information.

Principles

Provide Comparable Experiences: whether out of circumstance, choice, or context, people are diverse. Make sure that interfaces provide a comparable experience for all regardless of where or how they are interacting with us.

Consider Situation: first-time users, established users, users at work, on a couch at home, or on the move. Situational impact can create challenging interactions, especially for those with disabilities.

Create Consistency: use well-established patterns and familiar interfaces. Reinforce the meaning and purpose of our patterns by applying similar functionality, behavior, writing, and presentation of content.

Give Control: don't block users from having control over their browser, device, or platform. Settings such as orientation, font size, zoom, and contrast should be customizable by the user.

Offer Choice: provide more than one way to complete any given task by allowing for choice alternatives, setting the precedent that the user is in control of their experience.

Prioritize Content: unclear features and poor focus on interaction priorities can lead to difficult-to-understand and use interfaces. Prioritize levels of information, creating space for users to consume and interact with information or experiences, one at a time.

Global Accessibility Standards

Web Content Accessibility Guidelines

The Web Content Accessibility Guidelines (WCAG) are a set of guidelines defining accessibility standards for design and development of digital platforms. Implementation of WCAG guidelines ensures that digital platforms and content are inclusive.

The guidelines are updated every few years. The current version is WCAG 2.1. With each new version, new guidelines are added. Hence, a website that meets WCAG 2.1 criteria will also meet WCAG 2.0 criteria.

P.O.U.R.

While no two people experience disability the same way, no two barriers to accessibility are presented the same either. The Web Content Accessibility Guidelines group these barriers into principles known as P.O.U.R.—an acronym for four high-level principles that describe functional accessibility.

P.O.U.R. is the overarching structure of WCAG, where each requirement falls within one of these four pillars. While understanding each specific requirement can provide clarity in how to approach a specific accessibility problem, practicing the principle value of P.O.U.R. is a great place to start in understanding where these problem barriers begin, and what a solution may be.

• Perceivable: Information and user interface components must be presentable to all users. Web content that's primarily perceived visually should also have auditory or physical cues such as a video that has audio descriptions provided.
• Operable: User interface components and navigation must be operable to all users. For web content, that may mean a user interface is primarily navigated with a cursor, but content is also navigable by a keyboard alone.
• Understandable: Information and the operation of user interfaces must be understandable to all users. For web content, that may mean that instructions or labels are included when that content requires user input.
• Robust: Content must be robust enough that it can be interpreted by a wide variety of devices and assistive technologies, so that as technology advances, users can access content reliably. For web content, this means that standard HTML controls are met and content is implemented in a consistent markup language.

Resources

Evaluation Tools

WAVE Web Accessibility Evaluation Tools

Lighthouse overview - Chrome for Developers

Accessibility Insights

Color Contrast Tools

Stark: The suite of integrated accessibility tools for your product design and development team