What is a JPEG?

JPEG takes it's name from the Joint Photographic Experts Group who devised the standard in 1986, gaining final permission in 1994.

It is the most commonly used way to compress colour and grayscale continuous images, most commonly photographic images and is the format used by most digital cameras. JPEGs are a popular way to transfer images across the web and place images on web pages. They require minimum bandwidth compared to alternative image formats and make page loading speed much quicker.

One of the main disadvantage of using JPEGs in design work is that they don't respond well to frequent editing and compression. Each time the JPEG format is changed, image information is lost and cannot be restored. This can affect image quality. A JPEG also doesn't work well on line drawings, lettering or simple graphics. JPEGS have a hard time with sharp edges and these can come out blurred unless high quality settings are used.

Original Image as JPEG

Same image after repeated compression as a JPEG

Original image after compression as a PNG

Given the opportunity, it is best to compress and save images as a GIF or PNG, which is a format that will not lose graphic quality.

WORTH A READ - GIF VERSUS PNG