JPG stands for “Joint Photographic Experts Group”, which is why the extensions for these files will sometimes be .jpg and sometimes .jpeg.

It is a lossy-compression format, meaning that it relies on compressing data with some loss of quality or information.


JPEG2000, while sharing the same name, is a different compresion algorithm altogether. It is usually regarded as having a better compression ratio than JPEG alone, and was created as a successor of the JPEG format.