A few points about .PNG: It was never developed to compete with JPEG for hi-depth images and the PNG FAQ makes a point that file compression is not even comparable. PNG was meant to replace GIF once Unisys patented the compression algorithm it uses and required developers to get licenses. Browser makers have been reluctant to support PNG because it currently has multiple dialects and no governing committee or a Linus Torvalds to rein them in. OTOH if your browser has the QuickTime plugin you can view most PNGs with little difficulty. Special features like the alpha channel may not be supported, however. When PNG coalesces into a stable format, browsers will be certain to support it natively.