This applet allows you to do tasks that are not possible with animated gifs . This allows you to assign a unique URL to a frame or frames in the display. This lets you show for example various items available on your site. When the visitor clicks on an item it will take them to that item's page. The applet can even pause when the visitor moves the mouse over the applet and display info in the status bar about the item.
Animation is even smaller in file size than an animated gif.
You can take an image and change it's size, location, or zoom it in or out and the applet only needs one image for this. In an animated gif, you'd have to have multiple images and the download size would increase with each frame of animation. Here the applet downloads the image once and then manipulates it on the display. Another unique feature is that you can have jpg files for animations. Since jpgs are smaller in file size than gifs, this will also reduce the animation size further.