The Trivial File Transfer Protocol (TFTP) is used to transfer files between the TFTP client and a TFTP server, a computer running the tftpd TFTP daemon.
This protocol uses UDP as a transport and, unlike FTP, does not require a user to log on to transfer files.
Because TFTP does not require a user logon, it is often considered a security hole, especially if the TFTP server permits writing.