FTP MirrorAn FTP mirror is a site that copies, or mirrors the files from another FTP site. A mirror contains a complete copy of the original site and is frequently updated to match the main site. It reduces Internet traffic by moving popular information closer to the people who want to access it. Mirror sites also make it possible for more people to access the information at the same time.
When a major site gets new software, it can be overwhelmed by people trying to get onto the system to download the latest version of the software; when ones use a mirror site, usually there is less congestion.