Aria2
Aria2 is a lightweight, multi-protocol, and multi-source command-line download utility that supports HTTP/HTTPS, FTP, SFTP, BitTorrent, and Metalink. It is designed for high-speed downloading with features like segmented downloading, parallel connections, and resumable transfers. It is widely used for downloading large files, managing downloads in headless environments, and automating download tasks.
Developers should learn Aria2 when they need a reliable, efficient download tool for automation, scripting, or server environments where GUI tools are impractical. It is ideal for use cases like downloading software packages, media files, or datasets in bulk, handling resumable downloads for unstable connections, and integrating download functionality into applications or workflows via its JSON-RPC interface.