MBOXEmail Mailbox File
MBox file format is a generic term that represents a container for collection of electronic mail messages. The messages are stored inside the container along with their attachments. Messages from an entire folder are saved in a single database file and new messages are appended to the end of the file. Numerous applications and API provide support for MBox file format such as Apple Mail and Mozilla Thunderbird.
PNGPortable Network Graphic
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.