Question: If I had two divs, both with id="myDiv", would `$("#myDiv").fadeOut();` fade both divs out? Or would it fade only the first/second? Or none at all?

How do I change which one it fades out?

**Note:** I know duplicate id's is against standards but I'm using the fancybox modal popup and it duplicates specified content on your page for the content of the popup. If anyone knows a way around this (maybe I'm using fancybox wrong) please let me know.

Answer: 
Element IDs are supposed to be unique. Having multiple DIVs of the same ID would be incorrect and unpredictable, and defies the purpose of the ID. If you did this:

```
$('.myDiv').fadeOut();

```

That would fade both of them out, assuming you give them a class of myDiv and unique IDs (or none at all).
You can also go the route of using find(). find will return all the elements with that ID, and you can limit the scope to a particular parent if needed try something like `$(document).find('#myDiv').fadeOut();`

or 

```
$('.parentElement').find('#myDiv').fadeOut();

```