TypeScript

TypeScript enhances JavaScript with static typing and improved developer tooling. On this page, you’ll learn about types, interfaces, enums, generics, utility types, type narrowing, and advanced TypeScript patterns. You’ll also find interview questions focused on building scalable and maintainable frontend applications using TypeScript.

Basics

Fundamental concepts of TypeScript and its core principles.

Type System

Understanding static typing, type inference, and type checking.

Variables & Declarations

Working with let, const, readonly, optional, and definite assignment.

Functions

Typing functions, parameters, return values, and overloads.

Arrays & Tuples

Using typed arrays, tuples, readonly arrays, and spread operators.

Union & Intersection Types

Combining multiple types using union and intersection patterns.

Enums

Working with numeric, string, and const enums.

Type Guards & Narrowing

Runtime checks and custom type guards for safe typing.

Advanced Types

Mapped, conditional, indexed access, and literal types.

Generics

Reusable and flexible code using generics.

Utility Types

Built-in utility types like Partial, Pick, Omit, Record.

Classes & OOP

Object-oriented programming with classes and inheritance.

Interfaces vs Types

Differences, similarities, and use cases.

TypeScript

Basics

Type System

Variables & Declarations

Functions

Arrays & Tuples

Union & Intersection Types

Enums

Type Guards & Narrowing

Advanced Types

Generics

Utility Types

Classes & OOP

Interfaces vs Types

Modules & Namespaces

Asynchronous Programming

Type Assertions & Casting

Null & Undefined Handling

Configuration & Compiler Options

Decorators

TypeScript with Frameworks

Performance & Optimization

Best Practices

Testing & Tooling

Build & Deployment

Advanced & Edge Cases