RAW image format refers to the minimally processed image that a digital camera produces. When shooting in any other format, a camera will transcode the image data into its final form. RAW images, however, are comparable to film negatives; they have all the information that was captured when the picture was taken, and the quality and look of the image depends on how it is extracted.
RAW allows decisions of white point, exposure level, color cast, sharpness and saturation to be made in post, rather than locked in at the time of shooting, so that the photographer has the widest range of possibilities in how to process the image.
Though shooting in RAW can result in better quality images,they also have a far larger file size and require extra work as opposed to ready-to-use formats.