This format is used to create images without compression on Nikon Coolpix cameras. The created RAW files contain electronic data from the camera sensor. It is able to save more data compared with compressed photos. With NRW files you can set the exposure, white balance and other settings while preserving all the details in the image.
JPG extension was assigned to the image files. Many photos and web graphics are saved in JPG. In order to compress many bitmaps are saved in .jpg, that makes it easier to transfer and download these files on the Internet. JPG format based on the 24-bit color palette, the higher the level of compression applied to create the file JPG, the greater the decompression effect on image quality.