Blindness

What is Blindness?

Legal blindness and total blindness are not the same thing. Legal blindness is typically defined as visual acuity of 20/200 or worse in the better eye with best correction, or a visual field of 20 degrees or less. Total blindness means no light perception at all. Most people who are legally blind have some remaining functional vision.

Common causes of blindness include glaucoma, macular degeneration, diabetic retinopathy, cataracts (particularly in low-income countries where treatment is unavailable), retinitis pigmentosa, and traumatic injury. Blindness can be congenital (present from birth) or acquired at any point in life.

According to the World Health Organization, approximately 43 million people worldwide are blind, with a far larger number experiencing significant visual impairment. In many regions, the majority of blindness is preventable or treatable.

How It Presents

Functional impacts of blindness vary depending on when vision loss occurred, the person's environment, and the support and technology available:

• People blind from birth develop alternative strategies for navigation, reading, and social interaction from childhood
• People who become blind later in life may draw on visual memories and often have different adjustment challenges
• Orientation and Mobility (O&M) training teaches independent navigation using white canes and other strategies
• Reading and writing are typically supported through Braille, audio, or digital screen-reader access

Blindness does not affect intelligence, personality, hearing, or any other cognitive or sensory capacity — though the broader society often makes incorrect assumptions in this area.

Assistive Technology

The blind community has been at the forefront of AT development for decades:

• Screen readers — software such as NVDA, JAWS, VoiceOver (Apple), and TalkBack (Android) convert on-screen text and interfaces to synthesized speech or Braille output. These are essential for computer and smartphone access.
• Refreshable Braille displays — hardware devices connected to a computer or phone that translate digital text into tactile Braille
• Braille note-takers — dedicated portable devices for reading and writing in Braille
• White canes — the primary mobility aid for navigation; also serve as a social signal that the user has a visual impairment
• Guide dogs — trained mobility aids that provide navigation support and have legal access rights in most jurisdictions
• Talking devices — watches, clocks, and appliances with audio output
• AI-powered description tools — apps such as Seeing AI and Be My Eyes (with AI features) can describe photos, read printed text, identify products, and narrate the environment
• Accessible GPS and navigation apps — BlindSquare, Nearby Explorer, and accessible Google Maps features support independent travel

Common Misconceptions

• "Blind people cannot use computers or smartphones." Screen readers and accessible design make digital technology fully usable — provided developers build accessibly.
• "Blind people all read Braille." Braille literacy varies widely; many blind people rely on audio (screen readers, audiobooks) as their primary reading method.
• "If someone can see a little, they are not really blind." Legal blindness encompasses a wide range of visual function; someone can be blind by legal definition while still perceiving light or large shapes.

Language and Identity

The blind community generally uses identity-first language ("blind person" rather than "person with blindness"), though individual preference varies. Many blind individuals and organizations, including the National Federation of the Blind (NFB), actively use "blind" as a neutral, descriptive word — neither shameful nor something requiring softening with terms like "visually challenged."