Raw Photo Processor (RPP) is a RAW converter, supporting almost all available digital RAW formats. Think of it as of a development machine in terms of film photography - first you have to develop your roll right, then do whatever you want with it. So this is NOT a full featured photo processing package, you will need Photoshop or some other tool to apply sharpness, cropping and so on, but you may use RPP for some very carefully picked amount of operations.
The main idea behind this application is to do quality conversion without blocking shadows, clipping highlights, spoiling colors and returning that natural film-like look to your pictures.