Name and reuse types.
✍️ 3 exercises + code challenge in this lessontype Point = { x: number; y: number };interface User { name: string; age: number }interface Admin extends User { role: string }Both work for object shapes; type aliases can also name unions and primitives.
Mastering TypeScript Type Aliases & Interfaces helps you write clean and reliable TypeScript code. Follow standard conventions, test edge cases, and keep logic simple. Try running the code example below and complete the exercises to build confidence.
type Point = { x: number; y: number };
interface User {
name: string;
age: number;
}
interface Admin extends User {
role: string;
}
const p: Point = { x: 3, y: 4 };
const admin: Admin = { name: "Ayesha", age: 30, role: "owner" };
console.log(p.x + p.y, admin.name, admin.role);7 Ayesha owner
Check what you learned in “TypeScript Type Aliases & Interfaces”.
Declare an interface.
User { name: string; age: number }
How do you extend an interface?
Define interface Student { name: string; grade: number }, create one for "Sara" with grade 92 and log "Sara: 92".
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