JPG files, also known as JPEGs, are a common file format used primarily for digital photographs and other complex still images. JPG is pronounced jay-peg and stands for Joint Photographic Experts Group, the committee that created the file type. JPG files have the file extension .jpg or .jpeg and are, in fact also called JPEGs. They are the most common file type for images taken with digital cameras and are widely used for photos and other graphics used on websites.