JFIF is a raster graphic format that uses JPEG image compression algorithm. JPEG is a lossy compression method that sacrifices some original information but in a way that viewer cannot or barely can tell the difference between the original image and JPEG image. JPEG file are smaller in size because of used compression.

JFIF files use very effective compression method and thus are ideal for web-related uses where image (or any data for that matter) size is crucial. JPEG compression level can be adjusted according to user’s needs.