This Python tutorial book is a collection of notes and sample codes written by the author while he was learning Python language himself. Topics include: installing Python environments on Windows, macOS and Linux computer; Python built-in data types; variables, operations, expressions and statements; user-defined functions; iterators, generators and list/set/dictionary comprehensions; modules and packages; sys, os, and pathlib modules; Anaconda Python environment manager; Jupyter Notebooks; NumPy, SciPy libraries. Updated in 2024 (Version v2.15) with minor changes. For latest updates and free sample chapters, visit https://www.herongyang.com/Python.