concat array javascript

let arr1 = [0, 1, 2];
let arr2 = [3, 5, 7];
let primes = arr1.concat(arr2);

// > [0, 1, 2, 3, 5, 7]//for ES5
var array1 = ["Rahul", "Sachin"];
var array2 = ["Sehwag", "Kohli"];

var output = array1.concat(array2);
console.log(output);

//for ES6, we use spread operators to concat arrays

var array1 = ["Dravid", "Tendulkar"];
var array2 = ["Virendra", "Virat"];

var output = [...array1, ...array2];
console.log(output);
var array = ["Joe", "Kevin", "Peter"];
array.join(); // "Joe,Kevin,Peter"
array.join("-"); // "Joe-Kevin-Peter"
array.join(""); // "JoeKevinPeter"
array.join(". "); // "Joe. Kevin. Peter"var array1 = ["Vijendra", "Singh"];
var array2 = ["Singh", "Shakya"];

console.log(array1.concat(array2));
// output: ["Vijendra", "Singh", "Singh", "Shakya"]//turns array to string

const elements = ['Fire', 'Air', 'Water'];

console.log(elements.join());
// expected output: "Fire,Air,Water"

console.log(elements.join(''));
// expected output: "FireAirWater"

console.log(elements.join('-'));
// expected output: "Fire-Air-Water"
const letters = ['a', 'b', 'c'];
const numbers = [1, 2, 3];

const newArray = letters.concat(numbers);
// newArrat is ['a', 'b', 'c', 1, 2, 3]