TypeScript quiz

Test your TypeScript knowledge with a free interactive quiz — 51 questions with answers and explanations. No signup needed to play.

What is a union type in TypeScript?

1. What is a union type in TypeScript?
2. What does the `readonly` modifier do in TypeScript?
3. What is a tuple type in TypeScript?
4. What does the `keyof` operator do in TypeScript?
5. How do you define an array type in TypeScript?
6. What is the `unknown` type and how does it differ from `any`?
7. Which TypeScript option enables the strictest type-checking?
8. How do you specify that a function parameter can be either a string or a number?
9. What file extension is used for TypeScript files with JSX?
10. What does `tsconfig.json` control?
11. What does the `Pick` utility type do?
12. What is the `enum` type in TypeScript?

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