The CR2 - Canon Raw Image File is exactly what it sounds like; it's a image crated by a Canon digital camera. This file stores uncompressed dated, so it has been unaltered in any way from the time it was captured. The image can be altered for white balance with a number of image editing software applications, including the stock software each Canon camera comes with. The software is fairly intuitive and simple to use. Each file is either saved as a Camera Image Format (CIFF) in older models, or a TIFF file on newer models.