Topic 1
Primitives
TypeScript builds on JavaScript by adding types, so we can describe exactly what kind of values a variable
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TypeScript exercises from beginner to advanced
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Curriculum
TypeScript learning path
16 topics in 4 parts. Start at the beginning or jump to the part you want to practise.
Part 1
TypeScript Foundations
Start with core types, typed functions, object shapes, and arrays.
Beginner · 4 topics
Topic 2
Functions Basics
Functions are how we structure behavior. In TypeScript, you can describe parameter types and return types so
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Object Types Basics
Objects model real-world entities. In TypeScript, you describe an object's shape by listing its properties
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Arrays
Arrays are ordered lists of values written as T[] or Array<T>: `typescript const numbers: number[] = [1, 2,
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Modeling Data
Describe possible values and reusable data shapes with unions, aliases, interfaces, and null safety.
Beginner · 4 topics
Topic 5
Union & Literal Types
Union types let a value be one of several possibilities, while literal types restrict values to exact
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Type Aliases
Type aliases give a name to any type so you can reuse it throughout your code: `typescript type UserId =
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Start Topic 7
Interfaces
Interfaces describe the shape of an object: `typescript interface User { id: number; name: string; email?:
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Start Topic 8
null & undefined
When strict null checks are on, null and undefined must be handled explicitly. This helps you avoid crashes
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Safe and Reusable Code
Handle uncertain values safely, narrow types, and write reusable generic code.
Intermediate · 4 topics
Topic 9
Type Assertions
Type assertions tell TypeScript how to treat a value. They do not change runtime behavior—they only affect
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Start Topic 10
any (vs unknown)
any turns off type checking completely. It spreads quickly through your code and hides bugs. Prefer unknown
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Start Topic 11
Type Guards & Narrowing
Type guards help the compiler figure out which shape a value has at a given point. When a check succeeds,
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Generics Fundamentals
Generics let you write components that work over many types without losing type safety: `typescript function
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Advanced Type Patterns
Combine function signatures, utility patterns, object types, and indexed access for larger programs.
Advanced · 4 topics
Topic 13
Functions: Call Signatures & Overloads
Functions are the heart of TypeScript programs. You can describe a function's shape with a call signature:
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Creating Types from Types (Utility Patterns)
Utility types help you reshape and remix existing types without rewriting them: `typescript type User = { id:
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Object Types (Deep Dive)
This deep dive builds on basic object types with advanced patterns: Intersections – Combine multiple types
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keyof, typeof & Indexed Access
This category links runtime values to static types using powerful type operators: keyof – Get all property
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