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Introduction to TypeScript

How this course works, what the workbench can do, and the chapter list.

This is a TypeScript course for the Swiftener TypeScript Playground. The official compiler (tsc) type-checks, then the result runs as JavaScript. Always console.log. Plain JavaScript belongs in Introduction to JavaScript.

Goal

Finish every chapter by running the copy-paste blocks. The last chapter is a typed kiosk total you can reuse.

How to take the course

  1. Keep this tutorial tab and the TypeScript Playground side by side.
  2. Wait until the compiler is ready (status is no longer loading).
  3. Copy an exercise, paste it as the whole editor, then press Ctrl+Enter (or Cmd+Enter).
  4. Always console.log a result.

What this playground can and cannot do

  • Can: TypeScript, console.log, type errors in the output, local drafts.
  • Cannot: Node.js require, installing npm packages, or relying on a network fetch.
  • Do not paste untyped JavaScript-only lessons here unless the chapter says so.

Sample files

  • sales.json — Nairobi kiosk rows

Chapter list