CS50
cs50.harvard.edu
Harvard University's introduction to computer science and programming, free online with full lecture videos, problem sets, and an active community.
Why it is useful
Consistently rated among the best introductory CS courses available anywhere — free or paid. The production quality of the lectures, the rigor of the problem sets, and the breadth of languages covered (C, Python, SQL, JavaScript, HTML/CSS) make it significantly more comprehensive than typical coding bootcamp intros. The certificate is also free to earn through edX.
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