Free, peer-reviewed textbooks for introductory college and AP-level subjects from a nonprofit at Rice University.
OpenStax publishes openly licensed textbooks in math, science, social sciences, business and the humanities. Books can be read online or downloaded as PDFs at no cost, with low-cost print editions also available.
Yes, the online and PDF versions are free; print copies and some partner tools cost money.
Subject-matter authors, with peer review, coordinated by the OpenStax nonprofit at Rice University.
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