create javascript array with size code example

Example 1: array length javascript

var arr = [10,20,30,40,50]; //An Array is defined with 5 instances

var len= arr.length;  //Now arr.length returns 5.Basically, len=5.
console.log(len); //gives 5
console.log(arr.length); //also gives 5

Example 2: create array initialize size javascript

const array = new Array(4);
array.length //4