It was originally developed on [X11] by two students, Peter Mattis and Spencer Kimball, who wanted a graphical editing program. It has since not only become a serious graphical editor for such tasks as photo retouching, image composition and image authoring with [Port]s to [Windows] ([GIMP/Win32 | http://www2.arnes.si/~sopjsimo/gimp/]) and [MacOSX] ([MacGIMP | http://www.macgimp.org/], which costs £10), but has also forked off the GimpToolKit, the most successful [GUI] ToolKit on [Linux] and other [Unix]oid systems. 

  

 [TheGIMP]'s user interface is a very powerful, non-[MDI] design. WellUsedRhetoric says that AdobePhotoshop users will find it difficult to get to grips with the interface -- it suffers from the inevitable "It's almost, but not quite, entirely like AdobePhotoshop" complaints. There is an entire page devoted to this topic at GimpVersusPhotoshop. The interface will let you be extremely productive once you get to know it. Don't be put off by first impressions -- [read a book | http://www.gimp-savvy.com], or [post a question | http://gug.sunsite.dk/forums/] if you need help. For those of you who actually find the unique interface intuitive and productive, or just want to learn more, there's [The GIMP User Group | http://gug.sunsite.dk/]. The curious can visit [a gallery of GIMP artwork | http://www.gimpforce.org/].