OpenStax
openstax.org
Peer-reviewed university textbooks you can read online or download as PDFs
No sign-up
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ocw.mit.edu
Publishes the real lecture notes, problem sets and exams from MIT courses.
Around two and a half thousand MIT subjects released with the material the enrolled students actually got: syllabus, lecture notes, assignments and, for a few hundred courses, full video lectures with solutions. There is no enrolment and nobody marking your work, so it suits someone who already knows which subject they need and wants the primary material rather than a guided path. The engineering, maths and computer science shelves are deep; the humanities are patchier.
Questions
Works the moment the page loads. No account, no email, no trial. No certificate, no instructor and no credit — and some older courses are just a syllabus and a reading list.
Yes. MIT OpenCourseWare sends your input to its own servers to process it. That is fine for public material; for anything containing personal data, use one of the on-device tools instead.
No certificate, no instructor and no credit — and some older courses are just a syllabus and a reading list.
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openstax.org
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