That’s right: in JavaScript, almost everything is an object. But these objects are bit different from what we see in Java, C++ or other conventional languages. An object in JS is simply a hashmap with key–value pairs. A key is always a string or a symbol, and a value can be anything including strings, integers, booleans, functions, other objects etc. So I can create a new object like this:

var obj = {}; // This is not the only way to create an object in JS

and add new key–value pairs into it:

obj['message'] = 'Hello'; // You can always attach new properties to an object externally

or

obj.message = 'Hello';

Similarly, if I want to add a new function to this object:

obj['showMessage'] = function(){

  alert(this['message']);

}

or

obj.showMessage = function() {

  alert(this.message);

}

Now, whenever I call this function, it will show a pop-up with a message:

obj.showMessage();

Arrays are simply those objects which are capable of containing lists of values:

var arr = [32, 33, 34, 35]; // One way of creating arrays in JS

Although you can always use any object to store values, but arrays allow you to store them without associating a key with each of them. So you can access an item using its index:

alert(arr[1]); // This would show 33

An array object, just like any other object in JS, has its properties, such as:

alert(arr.length); // This would show 4

For in-depth detail, I would highly recommend John Resig’s Pro JavaScript Techniques.