sftp server was widely used for secure file transfers in the past.
sftp stands for 'Secure File Transfer Protocol' and allows for secure file transfer over SSH.
To set up an sftp server on Ubuntu, update the package lists, install ssh and openssh-sftp-server, and make configuration changes in the sshd config file.
Create a new user with an attached sftp group, set permissions, and connect to the sftp server using sftp commands.