Learning Paths / Learn TypeScript

typescript
intermediate
9h estimated

Learn TypeScript

Go from basic types to advanced type-level programming, covering generics, utility types, and declaration files.

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Foundations

  1. 1

    Basic Types

    Annotate primitives, arrays, tuples, and any with TypeScript types

  2. 2

    Interfaces

    Define object shapes, optional properties, and extendable contracts

  3. 3

    Union Types

    Combine types with union, intersection, and discriminated unions

  4. 4

    Enums

    Named constants with numeric or string enum members

Type Safety

  1. 1

    Type Guards

    Narrow types with typeof, instanceof, in, and custom predicates

  2. 2

    Type Narrowing

    How control flow analysis refines union types down to a single member

Generics

  1. 1

    Generics

    Write reusable functions and types that work across type parameters

  2. 2

    Advanced Generics

    Constraints, defaults, inference, and variance patterns for reusable generic APIs

Advanced Types

  1. 1

    Utility Types

    Transform types with Partial, Pick, Omit, Record, and ReturnType

  2. 2

    Mapped Types

    Transform every property of a type with key remapping and modifiers

  3. 3

    Conditional Types

    Branch on type relationships with extends, infer, and distribution

Tooling

  1. 1

    Decorators

    Annotate and extend classes, methods, and fields with reusable decorators

  2. 2

    Declaration Files

    Author .d.ts files to describe types for JavaScript and ambient modules