A JPEG is suitable for using highly detailed images such as photographs, it also uses much smaller file sizes than a PNG and GIF, although you are paying the price of losing image quality. This file type does not support transparency and is the least suitable for creating icons/logos.
JPEG was created in 1992 and works much better with photographs or natural scenery. It does not work well with lettering, black and white images, cartoon images. JPEG is a "lossy" which means you will lose quality when compressed, the quality of the image cannot be restored after that.