Web Resources for Programming from First Principles

This page keeps source links outside the lessons so the modules remain easy to read.

Easy second explanation: learn the idea in another friendly way.
Official technical reference: verify syntax and exact language rules.
Practice resource: run or modify code yourself.

Core References

Easy second explanation: Python Tutorial
Official technical reference: Python Language Reference
Practice resource: Python Standard Library

Module 1: Data Types and Collections

Easy second explanation: Built-in types
Official technical reference: Data model
Practice resource: Create values in the Python REPL and inspect type(...).

Module 2 to 6: Higher-Order Functions, Standard Constructs, Iteration, Lambda Calculus, First-Class Functions

Easy second explanation: Functional programming HOWTO
Official technical reference: Expressions and statements
Practice resource: Run map, filter, comprehensions, lambdas, and generator examples in Python.

Module 7 and 8: Type Discipline and Type Hints

Easy second explanation: Type hints in the Python docs
Official technical reference: The typing module
Practice resource: Add annotations and check them with mypy or Pyright.

Module 9 and 10: User-Defined and Concrete Types

Easy second explanation: dataclasses
Official technical reference: class definitions
Practice resource: Define Student, Shape, and TrafficLight examples in Python.

Module 11 to 14: Recursion, Operational Semantics, Shared Behavior, Polymorphism

Easy second explanation: Recursion and algorithm thinking
Official technical reference: Execution model
Practice resource: Trace recursive functions by hand, then test them in Python.

Extra learning

How to use these links

Read the module's simple idea and worked example.
Answer the self-check without looking at the solution.
Open the easy resource if the idea is unclear.
Use the official reference for exact rules.
Run the practice in Python.