"The GNU Image Manipulation Program (GIMP) was originally
conceived in a computer science class as a project to build a
pixel-based image editor. After many years of development in the
open source community, the GIMP has matured into a remarkably
powerful image manipulation program with an extensive set of
features rivaling that of Adobe Photoshop. Although it lacks a few
key functions, the GIMP's exhaustive library of tools makes it
exceptionally well suited for professional digital image
production, for the Web or otherwise."
"The GIMP matches Adobe Photoshop tool for tool--though some
tools in the GIMP have different names or appear on different
menus. The GIMP's interface espouses a modular look that's also
similar to its proprietary cousin, using floating windows for
tools, options, brushes, and layers. One important difference is
that the GIMP doesn't support CMYK output as Photoshop does. The
GIMP does, however, provide a powerful scripting language that far
exceeds the capabilities of Photoshop's Actions for automating
complex tasks and converting batches of images...."
"The GIMP's toolset is as configurable as it is comprehensive.
For instance, when using brushes (custom shapes used for drawing
tools), you're not restricted to the GIMP's default selection. You
can easily add custom brushes of any size or shape to suit your
particular needs. In addition, you can extend the functionality of
the GIMP, like that of Photoshop, via plug-ins."