function in interface

interface Person {
  name: string;
  age?: number;
  hello(): void;
}

const p1: Person = {
  name: "hyun",
  hello: function (): void {
    console.log(`Hi, my name is ${this.name}`);
  },
};

const p2: Person = {
  name: "kim",
  hello(): void {
    console.log(`Hi, my name is ${this.name}`);
  },
};