Portable Network Graphics ( PNG ) file format - a new bit-mapped graphics format similar to GIF. Approved as a standard by the WWW consortium to replace GIF because GIF uses a patented data compression algorithm called LZW. In contrast, PNG is completely patent- and license-free. PNG is a bitmap compression method for image files. PNG supports 16.7 million colors, it is lossless and also supports index color, grayscale, true color, transparency, and is streamable. It is thus the best compression method (better than GIF or JPEG) for use on the web.