From the home page:
"Linux Mint's purpose is to produce an elegant, up to date and comfortable GNU/Linux desktop distribution."
Linux Mint is freely available, complete desktop oriented GNU/Linux distribution based on Ubuntu. It is compatible with Ubuntu software repositories with its own additions and replacements. It has its own desktop design and UI improvements and its own GUI administration tools.
Linux Mint is known to be designed for ease of use and maximal out-of-the-box functionality for desktop user. After installation you have for example working support for common media including most used proprietary codecs (flash, DVD playback, divx and so on).