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Harvard CS50

CS50 is Harvard University's introduction to computer science — widely considered the best free programming course ever made. It's rigorous, engaging, and taught by David Malan. The course covers C, Python, SQL, JavaScript, and more. Free to audit; certificate available for a fee.

Our Verdict

Harvard CS50 is the most rigorous free introduction to computer science available anywhere. David Malan is a world-class teacher, and the problem sets are genuinely challenging.

Pros & Cons

Pros

  • World-class instruction
  • Problem sets are genuinely challenging
  • Prestigious Harvard brand

Cons

  • Certificate requires edX payment
  • Significant time commitment

Best for

People who want the rigor of a real university course.

All Harvard CS50 Courses (7)

Harvard's introduction to programming using Python. Covers functions, variables, conditionals, loops, exceptions, libraries, unit tests, file I/O, and regular expressions.

36h
4.9
Details

Harvard's legendary CS50 introduction to computer science. Covers C, Python, SQL, JavaScript, and web programming. The most-enrolled university course in the world.

100h
4.9
Details

Harvard's web development course covering HTML, CSS, JavaScript, Django, SQL, and API design. Learn to build complex, data-driven web applications. Free to audit; certificate via edX.

84h
4.9
Details

Harvard's dedicated SQL course. Learn to design databases, write complex queries, use indexes, and work with SQLite, MySQL, and PostgreSQL.

30h
4.8
Details

Harvard's introduction to AI with Python. Covers search, knowledge representation, uncertainty, optimisation, machine learning, neural networks, and NLP.

30h
4.9
Details

Harvard's CS50 introductory course starting with Scratch and progressing to Java concepts. The most engaging introduction to programming available anywhere.

100h
4.9
Details

Harvard's introduction to cybersecurity for technical and non-technical audiences. Covers threats, authentication, networking, system security, and operational security. Free to audit; certificate available via edX.

30h
4.8
Details