GIMP is an acronym for the GNU Image Manipulation Program. which can be used for several purposes, such as image processing, composing images (image) and create images.
Broadly speaking GIMP function does not differ much from Photoshop.
This software can read almost all file formats: from standard JPG to PSD, we can also use plug in to add compatibility with other file formats. GIMP also has a range of basic features: cropping, rotation, color adjustment. Other important features that we find in Photoshop are also available here: curve adjustment, hue saturation, sharpening, channel mixing, layer masking, clone stamp, healing brush and level.
Supports many image formats, including JPG and PNG that we often use. This format can be opened in almost any image editor and image viewer. So there is no reason why the format is not compatible. For storage in raw format, Have own format file that is XCF. If necessary, you can also use the PSD format (standard Photoshop format).
For the use of more expert, with the nature of the source code Applications Image and image processing can be used to make processing or rendering images online by combining with CGI or other that allows us to process images online.