Portable Network Graphics
PNG is designed for on-line viewing applications, such as the World Wide Web, so it is fully streamable with a progressive display option. PNG is robust, providing both full file integrity checking and simple detection of common transmission errors. Also, PNG can store gamma correction and chromaticity data for improved colour matching on heterogeneous platforms.
Filename extension: .png.
RFC 2083. W3C PNG pages. PNG home page.
(1997-08-07)

