JPEG is a common image format that is used mainly for its adjustable graphic compression.
User can modify the compression level to output smaller size or better image quality, or a balance between the two.
JPEG viewers will allow users to access these file types and to display them at the full quality of the image, i.e. without losing any of the features of the compressed photo.
Even though image viewers typically do not support any editing, some JPEG viewers allow users to rotate or crop their pictures.