JPEG Network Graphics (JNG, /ˈdʒɪŋ/) is a JPEG-based graphics file format which is closely related to PNG: it uses the PNG file structure (with a different signature) as a container format to wrap JPEG-encoded image data. The chunk-based structure of JNG files is essentially the same as that of PNG files, differing only in the slightly different signature and the use of different chunks. JNG does not have a registered Internet media type, but image/x-jng can be used.