Mailing the story:

FTP and SFTP are great protocols for downloading files from a remote or local server, or uploading files onto the server. FTP will suffice for some situations, but for connections over the internet, SFTP is recommended. In other words, FTP is not secure to use over an internet connection, since your credentials and data are transmitted without encryption. The 'S' in SFTP stands for 'Secure' and tunnels the FTP protocol through SSH, providing the encryption needed to establish a secure connection.