Although pretty much outdated, the File Transfer Protocol (FTP) still plays a significant role. For 20 years, LFTP has offered a greatly expanded command set for the command line that handles secure transmissions, without being excessively difficult to handle.
FTP dates back to 1985. Designed for transferring files between two computers, FTP is a relic from the infancy of modern IT. Today it has lost much of its former importance, not least because of some serious security problems: It neither encrypts the FTP username and password, nor protects the data against manipulation during transfer.
FTP via SSL (FTPS) or SSH (SFTP) counteracts these weaknesses. The two methods are considered to be equally secure, and they encrypt both data and metadata during transmission. In most cases, SFTP proves to be more flexible and much simpler in practice.