Let's say you have a number of identical class elements:

One Title
Another Title
Brrrr
Zzzzzz

And you want to get a particular element from this list.

var myArray = $(".myClass");
var thirdElement = myArray[2];
console.log(thirdElement);
// 
Brrrr

But note, that myArray[2] is the HTML element, not an jQuery object. If you want to access it via jQuery, you'll have to "arm" it...

var myArray = $(".myClass");
var thirdElement = $(myArray[2]);
console.log(thirdElement);
// [
Brrrr
]

Interrating over a jQuery selected list can be done with the each() function:

myArray.each(function(i, element){
    var myElement = myArray[i];
    // this
    // element
}

myElement, element and this would all hold the same value at each iteration. i is obviously the index counter.

It's also described quite clearly at the jQuery Docs, but I think it's important enough to reiterate.