Generics are one of the most powerful features in TypeScript. They allow you to write flexible, reusable code while maintaining type safety.

## What are Generics?

Generics provide a way to create reusable components that work with multiple types rather than a single type. They allow you to define type variables that can be used throughout your code.

## Generic Functions

Generic functions allow you to define functions that work with any type while preserving type information.

## Generic Constraints

You can constrain generics to certain types using the extends keyword, ensuring that the generic type has certain properties or methods.

Learn how to use TypeScript generics to write reusable, type-safe code.

TypeScript Generics: A Practical Guide

This comprehensive guide covers 50 essential TypeScript interview questions that every TypeScript developer should know. These questions cover fundamental concepts, types, interfaces, generics, advanced types, and TypeScript best practices commonly asked in technical interviews.

## Core TypeScript Concepts

Understanding TypeScript's core concepts is essential. These questions test your knowledge of types, type inference, type annotations, and how TypeScript extends JavaScript.

## Types & Interfaces

TypeScript's type system is powerful. Master these questions to demonstrate your understanding of basic types, interfaces, type aliases, and when to use each.

## Advanced Types

Advanced TypeScript features include generics, utility types, conditional types, and mapped types. These questions test your ability to work with complex type scenarios.

## Classes & OOP

TypeScript enhances JavaScript classes with access modifiers, abstract classes, and interfaces. These questions cover object-oriented programming in TypeScript.

## Best Practices & Modern TypeScript

Production-ready TypeScript requires understanding best practices, module systems, decorators, and modern TypeScript features. These questions cover real-world TypeScript development.

Comprehensive collection of 50 essential TypeScript interview questions covering types, interfaces, generics, advanced types, and TypeScript best practices. Free TypeScript interview questions with answers. TypeScript interview prep guide.

TypeScript Interview Questions: 50 Essential Questions for Developers

Generics are what make TypeScript truly powerful. They let you write code that works with any type while still maintaining type safety. Once you understand generics, you'll write much better TypeScript code.

## What are Generics?

Generics are like variables for types. Instead of writing a function for strings, then for numbers, then for objects, you write it once with a generic type. TypeScript figures out the specific type when you use it.

## Basic Generic Syntax

The syntax is simple - use angle brackets with a type variable. You can name it anything, but T (for Type) is common. The function works with whatever type you pass in, and TypeScript checks it.

## Constraining Generics

Sometimes you want generics to have certain properties. You can constrain them using extends. This gives you flexibility while still ensuring type safety.

## Real-World Examples

I'll show you practical examples - generic functions, generic interfaces, generic classes. These patterns you'll use in every TypeScript project. Understanding generics is essential for professional TypeScript development.

Master TypeScript generics - one of the most powerful features. Learn how to write reusable, type-safe code that works with any type. Essential for building robust TypeScript applications.

TypeScript Generics: Write Reusable Type-Safe Code

One of the most common questions in TypeScript: should I use interface or type? The answer isn't always obvious, but understanding the differences helps you make the right choice.

## Interfaces Explained

Interfaces define the shape of an object. They're great for describing contracts - what properties an object should have. They can be extended and merged, which makes them flexible for building up complex types.

## Types Explained

Types are more flexible - they can represent objects, unions, intersections, primitives, and more. They're more powerful but sometimes less intuitive. Types can't be merged like interfaces.

## When to Use Interfaces

Use interfaces for object shapes, especially when you might extend or merge them. They're also better for declaration merging. If you're defining the structure of an object, interfaces are usually the way to go.

## When to Use Types

Use types for unions, intersections, mapped types, or when you need features interfaces don't support. Types are more powerful for complex type manipulations.

## Best Practices

I'll show you real examples of when to use each, and common patterns. Understanding this helps you write cleaner, more maintainable TypeScript code.

Understand the difference between interfaces and types in TypeScript. Learn when to use interfaces, when to use types, and why it matters. This knowledge helps you write better TypeScript code.

TypeScript Interfaces vs Types: When to Use Each

TypeScript comes with powerful utility types that transform existing types. Instead of writing complex type definitions from scratch, you can use these built-in helpers. They save time and make your code cleaner.

## What are Utility Types?

Utility types are built-in TypeScript types that transform other types. They take a type and return a new type with modifications. Think of them as functions for types.

## Most Useful Ones

Partial makes all properties optional, Required makes them all required, Pick selects specific properties, Omit removes properties, and Record creates object types. These cover most of what you need.

## Real-World Usage

I'll show you practical examples - making API request types optional, selecting specific properties, creating mapped types. These patterns you'll use constantly in TypeScript projects.

## Combining Utility Types

The real power comes from combining utility types. You can chain them together to create exactly the type you need. This is how professionals work with types.

Master TypeScript utility types - Partial, Required, Pick, Omit, and more. These built-in type helpers make working with types much easier. Essential knowledge for TypeScript developers.

TypeScript Utility Types: Built-in Type Helpers

Learn TypeScript for type-safe JavaScript development.

TypeScript Tutorials - Programming Guide

All TypeScript Tutorials

TypeScript Generics: A Practical Guide

TypeScript Interview Questions: 50 Essential Questions for Developers

TypeScript Generics: Write Reusable Type-Safe Code

TypeScript Interfaces vs Types: When to Use Each

TypeScript Utility Types: Built-in Type Helpers