TypeScript Interfaces

Interfaces describe the structure of an object — like a blueprint for what it should look like.

Imagine you're working with objects that follow a specific pattern.

Instead of repeating that pattern again and again, you can define it once using an interface.

It tells TypeScript:

“Any object using this interface must include these properties and types.”

Here’s a basic example of an interface:

interface User {   
    name: string;   
    age: number;   
   isAdmin: boolean; 
}

Now you can use it like this:

TypeScript will make sure all required properties are there — and have the correct types.

Sometimes not every property is required. You can mark them as optional with a ?:

interface Product {  
   title: string;   
   price: number;   
   description?: string; 
}

Now description is not mandatory.

Interfaces can be extended — you can build on top of them:

interface Employee extends User {  
    department: string; 
}

This creates a new type that includes everything from User plus new properties.

You can also use interfaces to define what kind of object a function expects:

function showUser(user: User) {   
   Console.log(`${user.name} is ${user.age} years old.`); 
}

Watch these YouTube tutorials to understand TYPESCRIPT Tutorial visually:

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