Project Gutenberg

The oldest mass digital-library project, founded by Michael Hart in 1971, offering tens of thousands of public-domain ebooks in plain text, HTML, and EPUB. Project Gutenberg titles are widely used as a free accessible-text source by people with print disabilities, and its affiliated Distributed Proofreaders initiative coordinates volunteer crowds that verify OCR output. Project Gutenberg texts are often the raw material for refreshable-braille production, screen-reader reading exercises, and studies of accessible-book workflows, though the plain-text format can lack the structural metadata (headings, lists, tables) that rich-text accessible formats like DAISY or EPUB with ARIA markup provide.