PNG (Portable Network Graphics) is a file format used for image compression. This format uses lossless compression and it is considered as the replacement for GIF image format. PNG files are used to store graphics on websites and it provides 8-bit transparency. PNG files cannot be animated like a GIF file but MNG file format (a file format related to PNG) can animate the images. Some operating systems like MacOS and Ubuntu stores the screenshots in PNG format by default.