MNG is mostly about animations. It can do other things, but lets focus on web-content. Why would we need MNG? Well, there's animated-GIFtm, and we should by now all be understanding why GIF has lost it's appeal. So PNG can replace single-image GIFs, and MNG can replace animated-GIFs. As simple as that.
libmng-1.0.5: description + notes
This package includes mng-view, a sample GTK+ application for viewing
The libmng home page and MNG Home Page have more information.
Developers intending to use this distribution for application development should be sure to read the information in FAQ 3.8.
To auto-install this package, go back and click on the respective install icon.