GIMP is an open-source, multi-platform graphics manipulation tool. It is a free tool that is used by both amateur and professional graphics designers around the world. The Mac OS X version uses X11 as its engine for graphics manipulation. GIMP is very powerful for a free app. It does things a little bit differently than giants like Corel or Photoshop, but some people like GIMP's approach best. Of course, GIMP supports layers, plug-ins, effects and the like. And it can be used for photo editing, graphic creation, etc. On the Mac OS X project page there are links to several plug-ins that can be installed and offer additional features to the app.
I rarely use applications like this. So my perspective as of a beginner user, who often uses this type of apps, is to crop images, resize them, convert them to other formats, etc. I remember that I installed GIMP, a couple of months after I got my first Mac, to use it for the aforementioned tasks. I also remember that he app didn't last a day on my Mac. The reason was simple. GIMP is not native-looking at all. It has a great interface and many tools. But the application wasn't suitable for Mac at all. I often found myself having to double-click on tool icons for them to work or hitting a hot-key that didn't work because GIMP uses the control key instead of the command key. All those small annoyances made me switch to easier-to-use applications that didn't have the power of GIMP, but were more responsive. I am not saying that GIMP isn't an excellent application. I am just saying that it didn't satisfy my needs.
- Very complete
- User interface isn't native at all
- It doesn't use standard hotkeys