TypeScript
TypeScript for JavaScript Developers
Learn TypeScript from basic annotations through reusable object types, narrowing, generics, and safe application boundaries.
This is one technology path. Learn React, Next.js, Node.js, JavaScript basics, and future tracks separately at your own pace.
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Topics this track covers
static type checkingtype inferenceannotationsprimitive typesarrays and tuplesreadonly datafunction typesobject typesinterfacestype aliasesoptional propertiesunionsliteral typesnarrowingdiscriminated unionsgenericsconstraintsutility typesunknown and neverdeclaration files
1
TypeScript Foundations
Understand what TypeScript checks and add useful types without fighting the language.
- Why TypeScript exists - 8 min
- Inference and annotations - 8 min
- Arrays, tuples, and readonly data - 8 min
2
Modeling Real Application Data
Use object types, unions, narrowing, and generics to model changing application states.
- Object types and interfaces - 8 min
- Unions and narrowing - 8 min
- Generics and reusable constraints - 8 min
3
Advanced Type Modeling
Transform and compose types while keeping application states precise.
- Utility and mapped types - 8 min
- Conditional and indexed access types - 8 min
- Exhaustive discriminated unions - 8 min
4
TypeScript at Application Boundaries
Use TypeScript safely with external data, modules, React, and library declarations.