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The utility downloads files from HTTP/HTTPS, FTP, SFTP, BitTorrent and Metalink sources, allowing multiple connections per host and simultaneous use of several mirrors to maximize bandwidth. It can be invoked from the command line with simple URLs or a list file, and supports segmented downloading, selective BitTorrent pieces, and magnet links.

Its design emphasizes low resource consumption, typically using only a few megabytes of RAM and modest CPU load even when handling high‑speed BitTorrent transfers. The program also offers built‑in remote control through JSON‑RPC and XML‑RPC interfaces, enabling external scripts or applications to manage downloads programmatically.

Additional features include full BitTorrent support (DHT, PEX, encryption, web‑seeding, local peer discovery, UDP trackers) and Metalink handling for file verification and language‑specific selections. The software is open source, released under the GNU GPL, and available for Windows, macOS, Linux and Android.