When JPEG is referred to as a lossy format, it just means to say that the image data is lost when the image is compressed. JPEG stands for Joint Photographic Experts Group and is sometimes also referred to as JPG or JPE. It is a standard developed to handle color digital images and works best with photographic images rather than images of text mainly because it relies on the blending of color. Being a lossy format, JPEG compresses the image by blending redundant image pixels. Blurriness appears around edges of the objects in the photo as the image is compressed.

An image that has been compressed in JPEG format cannot be uncompressed. This is the reason why the original photo or digital negative should be taken with as little compression as possible. The use of JPEG as an editing original presents a problem in photo degradation on save even at the highest quality setting.