This article explains the basic features of gimp, where to find them and what they offer.  Thanks to About.com for this article.

Anatomy of GIMP

The Tools and Features of Free Pixel-Based Image Editor GIMP

By Ian Pullen, About.com Contributing Writer

GIMP is a popular and powerful open source pixel-based image editor that can be downloaded for free by anyone. It’s often referred to as a free alternative to Adobe Photoshop and one thing, among many, that it has in common with Photoshop is a potentially steep learning curve.

This is a result of the wide range of tools and features available to GIMP users. It isn’t unusual for GIMP users to quickly find the tools that they need regularly and then overlook many other exciting features. Here I’m going to take a run through GIMP’s user interface and take a brief look at the various groups of tools and features available and how they’re presented in GIMP’s interface.

GIMP doesn’t offer a universally popular user interface, with many finding it’s system of floating palettes counter intuitive, but the tools and features are easily accessible and there are many options for presenting tools in a personally preferred way. These tools and features are presented in three different ways, either through the Toolbox, rafts and dockable dialogs or the Menu bar.

Toolbox

The Toolbox is the primary way to select from the various main tools for working directly with images within GIMP. The toolbox isn’t the only way to select tools, but it is probably the most convenient, with the various tools’ options displayed below the Toolbox when a tool is selected. The same tools can also be accessed through the Tools menu item and also through the Tools dockable dialog, though the latter seems a little superfluous personally. Closing the Toolbox closes GIMP itself.

The various tools within the Toolbox can be grouped into several main groups.

• Selection tools – these offer different ways to select and isolate areas within an image so that they can be edited without affecting neighboring areas.
• Paint tools – these obviously cover tools such as the Paintbrush Tool and Pencil Tool, but also more advanced tools such as the Clone Tool and Blur/Sharpen Tool.
• Transform tools – tools that allow layers or selections to be transformed.

More: Anatomy of the GIMP Toolbox

Rafts and Dockable Dialogs

The Toolbox is the only palette that sits within its own raft. A raft is basically a floating window which contains a minimum of one dockable dialog or palette, but can be configured to hold multiple palettes. There is a raft below the Toolbox which, by default, contains the Tool Options dialog. The options displayed here change depending on which tool is currently selected.

It is possible to have a dockable dialog open in more than one raft at any one time and, in fact, you can even have the same dialog open multiple times within the raft, though it’s hard to see any reason for this.

Menus

The Menu bar contains several default menus, with some further sub-menus within these. The menus comprise of:

• File – commands for opening, saving and printing files
• Edit – contains the main commands for making basic changes to image files as well commands to edit the way that GIMP is configured
• Select – offers several commands for changing the way existing selections work
• View – all the commands affecting how both open images and the user interface displays information are contained here
• Image – commands for operating directly on the image as a whole, such as adjusting size
• Layer – range of commands for editing individual layers and their masks
• Colors – contains the full range of image adjustment commands
• Tools – most of the commands here can be accessed through the Toolbox or other menus
• Filters – contains a wide selection of filters by default and further filters can be added using plug-ins
• Windows – gives controls over dockable dialogs and open images
• Help – general help information about the GIMP installation including one click access to online resources

Once you look beyond GIMP’s slightly awkward interface, the various tools and commands within GIMP are presented in a pretty logical way. The biggest problem is arguably the sheer number of tools and features on offer, which can take a significant time to get acquainted with, but it can be hugely rewarding to experiment with the many tools and discover new techniques for working with your images.