Advantages

This offers some major advantages over just implementing XMLHttpRequest by itself:

1. Browser Support: This implements both XMLHttpRequest and a custom-written hidden-IFRAME-based transport layer. Therefore, it works in a wider range of browsers, including Opera 7 and IE5/Mac.
2. Accessibility: The document interface code is written with modern "best practice" coding standards in mind. Links are standard A HREF links with a CLASS attribute applied, so legacy useragents can still access your site's content.
3. Multithreading: The threaded RemoteFileLoader object will automatically create transports as needed, so you can have as many simultaneous requests going on in the background as you want. Plus, it's smart enough to reuse transports that are idle or loading into the same target.
4. Easy: You can load any file anywhere with just a function call.