Visual impairments or disabilities are defined by the National Eye Institute as corrected vision of 20/40 or worse. This is generally categorized into 3 levels based on strength of vision - low vision/visually impaired (between 20/70 and 20/160), legally blind (between 20/100 to 20/200), and totally blind (lack of light perception) (taken from https://www.accreditedschoolsonline.org/resources/helping-blind-low-vision-students/). Some people with visual disabilities may use assistive technology, such as glasses or magnifiers, braille printers or screen readers, canes or seeing-eye dogs.