From LQWiki

In the Internet world of today, it is often necessary to copy files over the Internet (uploading or downloading). This was what FTP was invented for; it allows easy file transfer over the Internet. However, as common as FTP is, it is completely unsecured - it is very easy for someone in the middle of the connection with a packet sniffer to intercept your files, username, and password. Fortunately, with the advent of the SSH protocol, it is possible to initiate a completely encrypted connection from a SSH client to a SSH server. (See the Using SSH page for more information about SSH.)

See scp or sftp for usage information on how to use these tools.