Digital Text 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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Digital text is delivered on a computer or another device to meet the needs of students with sensory, physical, or learning and reading disabilities. Digital text is malleable and, depending on the technology and/or the software that is used, various features that control how the content is presented to the user can be manipulated such as size, fonts, colors, and contrast to accommodate the needs of the learner. Supported reading software with text-to-speech can provide audio and visual components either separately or simultaneously as well as other scaffolded supports like highlighting, dictionaries, and thesauruses.
When digital text is delivered via accessible technologies, it can be of benefit to students with many different types of needs. Those with reading and learning disabilities often benefit from the use of supported reading software. Students with physical disabilities are able to access the content using various assistive technologies. Students who are visually impaired or blind may need the digital text content delivered via the computer as enlarged text on the screen or as refreshable braille.
New technologies combined with digital text make audio-supported reading (ASR) possible. This method is a technology-based approach for accessing and working with text that enables users with visual impairments to listen to voiced text while looking at screen-displayed print or using a refreshable braille device. With sufficient practice, both braille readers and magnified print readers can greatly increase the rate at which they can obtain information from text using ASR. This method also holds great promise for other students with reading and learning disabilities.