spread operator in javascript

                                    let arr1 = ['A', 'B', 'C'];

let arr2 = ['X', 'Y', 'Z'];

let result = [...arr1, ...arr2];

console.log(result); // ['A', 'B', 'C', 'X', 'Y', 'Z']
// spread elements of the array instead of taking the array as a whole

                                    function sum(x, y, z) {
  return x + y + z;
}

const numbers = [1, 2, 3];

console.log(sum(...numbers));
// expected output: 6

console.log(sum.apply(null, numbers));
// expected output: 6

                                    var myName = ["Marina" , "Magdy" , "Shafiq"] ;const [firstName , ...familyName] = myName ;console.log(firstName); // Marina ;console.log(familyName); // [ "Magdy" , "Shafiq"] ;

                                    const parts = ['shoulders', 'knees']; 
const lyrics = ['head', ...parts, 'and', 'toes']; 
//  ["head", "shoulders", "knees", "and", "toes"]

                                    obj = {first_name : "Marty",
    lovers: ["Jennifer Parker","Baines McFly"]
      };
let objClone = { ...obj }; // pass all key:value pairs from an object 

console.log(objClone)
// { first_name: "Marty", lovers: ["Jennifer Parker", "Baines McFly"] }