JavaScript and TypeScript

Appearance

JavaScript and TypeScriptA course for experienced programmers

Build a precise mental model of the languages, runtimes, browser, React, and modern tooling.

Start the course
Browse all articles

  • JavaScript first

    Learn the language and runtime model before adding TypeScript or framework behavior.

  • Article based

    Read connected, long-form explanations with realistic examples embedded in the prose.

  • Complete path

    Progress from values and modules through asynchronous code, browser APIs, TSX, React, and tooling.

About this course ​

This course assumes you are already comfortable programming. Familiar syntax moves quickly; JavaScript- and TypeScript-specific semantics receive the detailed treatment.

There are no required assignments or exercise projects. Each article includes a small selection of optional prompts with reasoned answers for readers who want retrieval practice. Follow the articles in order and use the sidebar to move between course parts.