Raw files are saved and stored in the .DNG extension and retain all of the unprocessed data of an image. HEIC is Apple’s way for storing photos. It is not a format in itself, but a container for storing images. This means the images are of better quality and use less storage space. They are stored with a .heic extension. JPEG is the most common format to store photos. It's been in use for over a quarter of a century, it’s best featured for exporting photos as it has universal compatibility, and can be accessed by just about any device that can open images.