This overview introduces key concepts of writing for everyone.
Types of disability
Disability can be visible or invisible, and it can be situational, temporary, or permanent. The following table includes some examples.
| Vision | Hearing | Speech | Mobility | Cognition | |
| Situational | Driving Dark room |
Noisy environment | In a library At a lecture |
In bed Arms/hands full |
Forgetting information Time demands |
| Temporary | Dilated pupils Cataracts |
Ear infection | Laryngitis | Arm or hand injury | No prior training Multi-tasking |
| Permanent | Blindness Vision impairment |
Deaf Hard-of-hearing |
Dysarthria Stuttering |
Amputation Parkinson's disease |
Dementia |
According to the World Health Organization, about 16% of the world's population experiences significant disability. However, as the preceding table illustrates, disability shows up in various ways and can affect anyone at different times in life. Designing for everyone does indeed benefit everyone.
The curb cut effect
Designing for everyone often results in benefits beyond the intended use cases.
The curb cut effect is a common example of beneficial design in the physical world. Originally, curb cuts (sidewalk ramps) were designed for people in wheelchairs. However, many people benefit from curb cuts, such as anyone with a stroller, suitcase, or delivery cart.
Here are some other examples of the curb cut effect in digital technology:
- Contrast ratios: Color contrast requirements were originally designed to help people who have low vision or color blindness. Color contrast requirements also ended up helping people who are trying to see the phone screen on a sunny day, or who had their pupils dilated at the eye doctor.
- Text to speech and voice commands: These tools assist people who are blind or have low vision. They also turned out to be useful for hands-free use while driving, cooking, or holding a baby.
- Keyboard access: Improving keyboard navigability improves accessibility for screen reader users and people with motor impairments. Keyboard access also improves productivity for power users.
- Clear language: Simplifying language makes documentation easier to understand, and it also eases translation and localization.
Next unit: Write helpful alt text