Visual Impairment Glossary

Vision impairment and blindness, its causes, and assistive resources come with a huge range of terminology. Browse our glossary to learn the meanings of these terms. 

Fingers type on a BrailleNote touch
Browse the glossary using this index

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This refers to the ability of humans to detect objects in their environment by sensing echoes coming from those objects. By creating sounds – like tapping canes, stomping their foot, snapping their fingers, or making clicking noises with their mouths – people with this training are able to know where they are in space by interpreting the sound waves reflected back to them from objects around them, accurately identifying their location and size. This ability is used by some visually impaired people to navigate within their environment using auditory rather than visual cues.


Using braille translation software, a document can be embossed (printed) using an embossing machine. Embossers usually need special braille paper which is thicker and more expensive than normal paper. Embossers can be either one-sided or two-sided printers.