aria2 is a lightweight multi-protocol & multi-source command-line download utility. It supports HTTP/HTTPS, FTP, SFTP, BitTorrent and Metalink, etc.
License: Open Source
FreeRapid Downloader is a user-friendly, Java-based tool primarily designed for downloading from file hosting services, while aria2 is a powerful command-line downloader that supports multiple protocols and offers advanced features for more experienced users. The choice between them depends on the user's preference for ease of use versus functionality and performance.