There is a secure equivalent of ftp on UNIX, Linux, MacOS, and Windows.
On Windows, click the yellow Secure File Transfer icon on your desktop, which
appeared after you downloaded and installed Secure Shell.
On UNIX, the secure commnd-line equivalent of ftp is called sftp.
On Mac PCs, use command-line sftp or download and install Fugu.
On Linux, command-line sftp should already be installed and in your default path.