declare object array in typescript

                                    //Define an interface to standardize and reuse your object
interface Product {
    name: string;
    price: number;
    description: string;
}

let pen: Product = {
  name: "Pen",
  price: 1.43,
  description: "Userful for writing"
}

let products: Product[] = [];
products.push(pen);
//...do other products.push(_) to add more objects...
console.log(products);
/* -->
*[
* {
*  name: "Pen",
*  price: 1.43,
*  description: "Userful for writing"
* },
* ...other objects...
*]

                                    export class CrudService {
  ...
  cards: Card[] = [];
  ...
}

                                    // Create an interface that describes your object
interface Car {
  name: string;
  brand: string;
  price: number;
}

// The variable `cars` below has a type of an array of car objects.
let cars: Car[];

                                    interface User {
	[index: number]: {
    	firstname: string;
      	lastname: string;
      	age: number;
    }
}

                                    let userTestStatus: { id: number, name: string }[] = [
    { "id": 0, "name": "Available" },
    { "id": 1, "name": "Ready" },
    { "id": 2, "name": "Started" }
];

userTestStatus[34978].nammme; // Error: Property 'nammme' does not exist on type [...]