College Open Text Books
Applied Science (Computer & Information Sc., Engineering & Electronics, Health & Nursing)
FreeTechBooks
Computer Science, Engineering and Programming
OpenStax College
Mathematics, Science, Social Science, Humanities
Project Gutenberg
Multidisciplinary - Over 60,000 free eBooks
Khan Academy
Science & Engineering, Arts & Humanities, Economics & Finance, Computing
Open Culture
Art History, Biology, Business, Chemistry, Computer Science, Economics, Engineering, History, Languages, Law, Mathematics, Music, Philosophy, Physics, Psychology, Sociology
OER Commons
Applied Science, Arts, Business, Education, English, History, Law, Life Science, Mathematics, Physical Science, Social Science
Open Textbook Library
Accounting & Finance, Business, Computer Science, Economics, Education, Engineering, Humanities, Law, Mathematics, Medicine, Natural Sciences, Social Sciences