EMZ is a file extension for a compressed graphics file used by the Microsoft Office Suite and Visio. Stands for Enhanced Metafile-Zipped. Contains an EMF (Enhanced MetaFile) image file that has been compressed using GZIP compression.
PNG, Portable Network Graphics, refers to a type of raster image file format that use loseless compression. This file format was created as a replacement of Graphics Interchange Format (GIF) and has no copyright limitations. However, PNG file format does not support animations. PNG file format supports loseless image compression that makes it popular among its users. With the passage of time, PNG has evolved as one of the mostly used image file format