Decorative images don't add information to the contents of the page. Therefore they:
- Don't need captions
- Don't have to meet color contrast guidelines
- Don't need alt text
- Should have a null (empty) tag (alt="") in the image label so screen readers skip them

Decorative Images

Informative images convey a concept in a short, digestive manner. Therefore they:
- Relay accurate information that is relevant to the adjacent text
- Need captions
- Need alt text if the caption or adjacent text does not explain the image
- Have to meet color contrast guidelines for essential items
- Contain essential and non-essential elements


Informative Images

Functional images are logos, icons, images within a button, and images that are actionable (ie. a link). The alt text for functional images is different than alt text for other types of imagery. This is because functional imagery depicts the function of the image, not its contents or what it looks like. When an image is within a button, add an alt tag that explains its function with an action verb.

Functional Images

Different image types will have different accessibility guidelines and different contexts on where it's appropriate to apply these guidelines.
- Decorative images
- Informative images
- Functional images

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- Assistive Technology
- Information Hierarchy
- Color and Contrast
- Accessible Layout
- Writing and Accessibility Text
- Imagery
- Sound and Motion

Elements of Accessible Design

Material Design Documentation

Organizing your information in a way that's intuitive helps users easily navigate through your app and help determine what's important. Information can be emphasized through things like color, shape, text, and motion to add clarity.

Information Hierarchy

Utilizing different colors and contrasts can help improve your user's ability to see, interpret, interact, and understand your app's contents. This is extremely helpful for those with low vision or colorblindness.

Color and Contrast

It's important to consider how your app scales content and responds to various devices and user inputs. These greatly influence the ability for your user to interpret and interact with your design.

Accessible Layout

It is important to structure your contents in a way that utilizes accessibility text or, text that is used by screen reader accessibility software. Screen readers are able to read aloud the on-screen text as well as assorted elements (ie. buttons), including both visible and non-visible alternative text.

Writing and Accessibility Text

Types of Imagery

Sound and motion can be incredibly helpful for users to help navigate through your page with or without a screen reader. However, accessibility for screen readers should still be considered when implementing these elements.

Sound and Motion

When using standard platform controls and semantic HTML, apps will automatically contain the markup and code needed to work with a platform's assistive technology. By meeting each platform's accessibility standards and supporting its assistive technology (ie. shortcuts, structure), you can give users an efficient experience. You can test your design with the platform's accessibility settings turned on - this should be done both during and after implementation.

Implementing Elements of Accessible Design

Devices that help maintain or improve the functional capabilities and/or independence of individuals with disabilities.

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