Adobe's Photoshop software is a very powerful image editing program that is by far the market leader for editing image files. I use Photoshop extensively when creating, and editing images for the web sites that I design. Almost all professional photographers and printers also use Photoshop to create all of the wonderful images that appear in magazines, billboards, and even on television. I am not the best artist in the world, but with Photoshop I have enough power to create brilliant images with tools that are built-in to the software.
The retouching plug-ins can intelligently change the contrast, color, sharpness, and many other common filters to make a picture look as crisp as possible. The special effects plug-ins are my favorite, because they can make a rather plain image into something fantastic. If you use Photoshop on a regular basis, then you need to look at some of the plug-ins that are available, because they can make your life much easier, and your graphics look much better.