Foundations

Introduction to JavaScript & Python

Programming fundamentals taught in both languages at once, so you learn to separate the concept from the syntax. Twenty-five modules from your first line of output through algorithms and complexity, with a live editor in every lesson.

The course project

Personal Knowledge Archive

The same conceptual application built in both languages, so you can feel exactly which parts transfer and which parts are only spelling.

course

25 modules · 77 lessons

Each module ends with a practice test, a graded build, and a step of the course project.

Level I

The Basic Idea of Programming

A program takes input, follows instructions, and produces output. You'll write your first one in the next five minutes.

Variables and Assignment

A variable is a named container for a value. Naming things is power. It always has been.

Data Types

Every value has a type, and the type decides what you can do with it. 42 and "42" are different citizens.

Strings and Text

Text is data. Names, stories, lyrics, records: learn to hold them, slice them, and reshape them.

Numbers and Arithmetic

From market math to algorithms: the seven operators, precedence, and the honest weirdness of floats.

Boolean Values and Comparisons

Two values, true and false, carry every decision a program will ever make.

null, undefined, and None

How programs represent nothing, and why nothing comes in more than one flavor.

Level II

Arrays, Lists, Objects, and Dictionaries

One variable holds one thing. Collections hold many, and that's where real programs begin.

Real-World Data

The moment syntax becomes usefulness: asking real questions of real datasets.

Operators and Logical Expressions

The full operator vocabulary, and how precedence decides what your code actually means.

Iterable Data Structures

What it means for data to be walkable: the idea every loop stands on.

For Loops

Write the instruction once. Run it for every item. This is where programs stop being calculators.

While Loops

For loops run a known number of times. While loops run until a condition changes.

Level III

Conditional Statements

if, else, and elif: how a program chooses a path instead of following one.

Functions

Name a piece of logic once, use it everywhere. This is how programs stop repeating themselves.

Scope and Lifetime

Where a variable can be seen, and how long it lives. The rule behind half of all confusing bugs.

Data Conversion and Parsing

Representation is not value. "42" and 42 look alike and behave nothing alike.

Working with Collections

Copying, sorting, nesting, and the reference trap that catches everyone exactly once.

Errors and Exceptions

Errors are not failure. They are the program telling you exactly what it needs.

Working with Files and JSON

How data survives after your program ends, and the format the whole internet agrees on.

Level IV

Algorithms and Problem Solving

An algorithm is a procedure for solving a problem. You have been writing them since Module 1.

Common Algorithms

Ten patterns that cover most of the problems you will ever be asked to solve.

Complexity and Efficiency

Why one correct program finishes instantly and another correct program never finishes at all.

A Practical Mini-Project

Everything at once: real data, real structure, real decisions, in both languages.

Quick Reference Mastery Review

Everything, side by side, one last time. This is the page you will keep coming back to.

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