The website design software Flash is great for simple, easy to navigate image galleries. Most photo galleries depend on pop-up windows or forward and backward buttons, making navigation cumbersome.
Flash avoids all of that. Instead, there are clear thumbnails which give you an idea of the image your are about to see, and the enlarged image opens right on the same page as the thumbnail. That way, you can skim through the thumbnails you want to enlarge, going back and forth at your leisure.
The idea is to keep your web audience as interested as possible, with the least amount of work. Too many buttons, non-visual navigation, and pop-up windows to close each time all take their toll, and many of those images you have for display may end up not being viewed.
Click here and here to see an example of a gallery designed with Flash.