Legendary programming books available free online. Read in your browser, download as PDF, or explore on GitHub — no paywall.
by Marijn Haverbeke
A modern introduction to JavaScript covering functions, closures, higher-order functions, OOP, and the browser. Widely regarded as one of the best free programming books.
by Al Sweigart
Learn Python by automating everyday spreadsheet, PDF, file, and web-browser tasks. Practical, project-based approach perfect for non-programmers.
by William Shotts
The authoritative guide to the Linux shell and command line tools. Covers Bash scripting, permissions, processes, and package management in depth.
by Kyle Simpson
A deep-dive series into JavaScript core mechanics: scope, closures, this, prototypes, types, and asynchronous patterns. Free on GitHub.
by Scott Chacon & Ben Straub
The official, comprehensive Git reference book co-authored by GitHub co-founders. Covers branching, rebasing, internals, and team workflows.
by Harvard University
Harvard's acclaimed CS50 lecture notes, problem sets, and slides — completely free. Covers C, Python, SQL, web development, and AI fundamentals.
by Jake VanderPlas
An excellent free reference for data science with Python. Covers NumPy, Pandas, Matplotlib, and Scikit-Learn with Jupyter Notebook examples.
by Allen B. Downey
An introduction to Python programming through the lens of computational thinking. Covers fundamental concepts from variables to classes and recursion.