High Quality Content by WIKIPEDIA articles! ABC is a free software, open source BitTorrent client based on BitTornado. It supports a queueing system with priority, global and local (per torrent) preference setting for downloading torrent (including upload and download rating limit), 3 upload options to do with completed file, and a system named Upload Rate Manager (URM) to force torrents out of queue if there is not a pre-set amount of upload activity. There is also an extensive web interface in ABC, allowing for other applications to view and change torrents and preferences remotely.