Why TypeScript? Benefits Over JavaScript, Explained
JavaScript finds mistakes when users hit them. TypeScript catches them while you type. What you gain, what it costs, and when it is worth it.
In this chapter
Why TypeScript?
Why TypeScript: common questions
Is TypeScript better than JavaScript?
TypeScript is JavaScript plus a type checker. It runs the same code but finds many mistakes in the editor, before users hit them. The cost is a build step and learning the type system.
Does TypeScript make code faster?
No. Types are removed at build time, so the JavaScript that runs is the same. The gain is fewer bugs and safer refactors.
More on Everyday types
- TypeScript Types: Primitives, Arrays and Tuples
- TypeScript Function Types: Parameters, Overloads, void
- TypeScript Interface vs Type Alias, and Object Types
- Structural Typing and Excess Property Checks in TypeScript
- any vs unknown vs never in TypeScript
- TypeScript readonly, as const and Type Widening
- TypeScript Classes: private, #private, abstract, implements
- TypeScript Enums vs Union Types: Should You Use Enums?
- Annotate or let TypeScript infer
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