TypeScript
BeginnerTypeScript adds a powerful type system on top of JavaScript, and this beginner course shows you exactly how to use it to write more reliable, self-documenting code. You will start with why types matter and how to set up a project with the TypeScript compiler, then learn the basic types, type inference, and the tsconfig options that shape how strict your project is. From there you go deep on the type system itself: union and literal types, type aliases, narrowing a value down to its real type, and the difference between any, unknown, and never. You will learn to write functions with typed parameters and return values, optional and default parameters, function overloads, and generics — the tool that lets one function or type work safely across many data shapes. You will model real-world data with interfaces and classes, understand access modifiers, and see how TypeScript's structural typing differs from what you may know from other languages. Finally you will explore utility types, mapped and conditional types, how modules and declaration files fit together, and the build tooling that turns TypeScript into JavaScript your browser or server can run. By the end you will read and write TypeScript with confidence in any modern codebase.
Course content
Certification Exam
Certification Exam
TypeScript
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Certification Exam
TypeScript
30 Questions
All difficulty levels
45 Minutes
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70% to Pass
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Tips
See allpaths Aliases Clean Up Deep Relative Imports
Trade `../../../utils/format` for `@utils/format`
satisfies Checks a Value Without Widening It
Get validation and precise inference in the same line
Pick and Omit Reshape a Type Without Rewriting It
Derive a smaller type instead of duplicating fields by hand
Partial<T> Turns Every Field Optional for Updates
The built-in utility type for PATCH-style payloads