Answer 1

JavaScript has keyboard var and let which automatically understand each data types like if you are taking number then var will consider it as number and when you are taking String then it will consider as String. For example:-

var = 10; //number
var = "AJ"; // String

var object = {}; //Object
var array = []; //Array

And

What do you mean by Smallest and Largest number of JavaScript? It should be "in JavaScript" not "of JavaScript".

If you want to find smallest and largest number in Array then sort the array in ascending order and get smallest number using array[0] and largest number using array[array.length - 1].