TypeScript — Beginner

TypeScript — Types That Protect Paid Work: 6 topics and 27 interactive cards with runnable examples and quizzes.

Topics

1. Why TypeScript Is Worth Your Time — The Bug the Client Finds First · TypeScript Is a Checker, Not a Runtime · Pin the Version: 5.9.3, Never latest · Check Yourself
2. The Types You Will Use Every Day — Let the Compiler Infer · Arrays and Objects · Union Types Close the Door · Literal Types Are Cheap Validation · Predict the Error
3. Describing Your Data Once — interface: One Shape, Reused Everywhere · type vs interface · Optional and readonly · Check Yourself
4. Functions That State Their Terms — Parameters and Return Types · Optional and Default Parameters · The Invoice Total · Fix the Bug
5. The Holes in the Fence — any Turns the Checker Off · unknown Makes You Prove It · strict Is Where the Value Is · Data From Outside Is Never Typed · Check Yourself
6. The Project You Set Up On Every Job — Three Files and a Build · What Each tsconfig Line Buys You · The Four Commands · Reading the Compiler's Complaints · What to Show a Client