MNG has advanced animation features which make it very useful as a full replacement for GIF animations. These features allow animations that are impossible with GIF or result in much smaller files as GIF.
As MNG builds on the same structure as PNG, it is robust, extensible and free of patents. It retains the same clever file integrity checks as in PNG.
MNG also embraces the lossy JPEG image-format in a sub-format named JNG, which allows for alpha-transparency and color-correction on highly compressed (photographic) images.
MNG 1.00, Februari 9, 2001:
Multiple-image Network Graphics (MNG) Specification Version 1.00 (Februari 9, 2001): Glenn Randers-Pehrson and others (firstname.lastname@example.org).