In this way, a magnet link can save much bandwidth on downloading files. These files can be generated by anyone who already has the file without a central authority. When you download a shared file from the P2P network through the magnet link, actually you download the file piece by piece from various servers which own part of the shared file. The magnet links allow files to be referred to without the need for a continuously available host. Magnet links are mainly used in P2P (peer-to-peer) file-sharing networks that are combined by several computer servers.
Before learning about how to download from magnet link using uTorrent or without using uTorrent, it would be best if you could get an overview of the magnet link and uTorrent.