png is often smaller then gif. and most times smaller then jpg. it has support for an alpha channel. it represents images better for people with 16bit colourdepth. it has a lossless compressiontechnique(you dont loose any information whatsoever, the image looks exactly as intended) but in larger sizes this format can be huge in filesize speaking, so there may have to be a size limit to this format, like 300kb or something. the reason i request this is because it would be great for thumbnails(try saving in png yourself), sometimes its great as a final image aswell, depending on how much the jpeg compression destroys the image)