What is it mainly used for?
The main intended purpose for JPEG is compression
of photographic still images. It has been adopted widely as an efficient electronic
means of transferring still images. For example, it is widely used on the Internet
and particularly the World Wide Web. It has also been used for video, multi-frame
moving images, by applying compression to each frame independently. There are certain
advantages to this form of video compression for real-time systems, such as less
delay between frames and no need for frame buffers, but it is less efficient than
other video compression systems such as MPEG_1 and MPEG_2.