FileZilla is open source  FTP client and server software distributed free of charge under the terms of the GNU General Public License.

Features of FTP client:

• Supports FTP, FTP over SSL/TLS (FTPS) and SSH File Transfer Protocol (SFTP)
• Cross-platform. Runs on Windows, Linux, *BSD, Mac OS X and more
• IPv6 support
• HTTP/1.1, SOCKS5 and FTP-Proxy support
• Network configuration wizard
• Configurable transfer speed limits

Download FTP client from here

Download FTP server from here