FileZilla
FileZilla is free and cross-platform FTP software, consisting of FileZilla Client and FileZilla Server. Binaries are available for Windows, Linux, and Mac OS X. It supports FTP, SFTP, and FTPS (FTP over SSL/TLS). As of 18 April 2011, FileZilla Client was the 7th most popular download of all time from SourceForge.net. Support for SFTP (SSH File Transfer Protocol) is not implemented in Filezilla Server.
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