Braille is one of the four accessible formats that may be used by people with a print disability.
According to the National Center on Accessible Educational Materials 
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Braille is a tactile system of reading and writing made up of raised-dot patterns for letters, numbers, and punctuation marks. This format is used almost exclusively by people who are blind or whose eyesight is not sufficient for reading printed material. Braille may be either embossed (a permanent printed document) or refreshable (electronically generated and accessed via a braille display device). The process of learning to read in braille is similar to learning to read and write print., People typically use the fingers of both hands to read from left to right over a line of braille using very little pressure with their fingers to touch the braille dots. Tactile perception and discrimination skills are important for efficient braille reading.
In order to determine if braille might provide a student with a visual impairment with the best means to develop literacy skills to access information and participate in all educational activities, the decision making team initiates a systematic and objective evaluation process. This process includes information from a variety of sources, such as a clinical low vision evaluation, a functional vision assessment, a learning media assessment, and the student’s progress in the educational program. The team analyzes and considers the information in a variety of contexts, including the student’s current and future needs before determining that braille might be the primary learning medium. Students who use braille may also need other specialized formats for different subjects or contexts.