A TORRENT file contains information about a file that can be downloaded from BitTorrent servers on the Internet. When a torrent file is accessed in a Web browser, it should open within the default BitTorrent client that is installed on your system. If no BitTorrent client is installed, the TORRENT information file may download within the browser, but nothing else will happen.
About BitTorrent, Inc. BitTorrent
BitTorrent is a protocol that allows users to download files from multiple servers at a one time. This provides faster download speeds, especially for big files, since the bandwidth is not limited by a single server. The BitTorrent Client program allows users to download torrents and upload torrent data to other BitTorrent users simultaneously.