The Trivial File Transfer Protocol (TFTP) is the stripped-down, stock version
of FTP, but it’s the protocol of choice if you know exactly what you want and where to find it. It doesn’t give you the abundance of functions that FTP does, though.
TFTP has no directory-browsing abilities; it can do nothing
but send and receive files.
This compact little protocol also skimps in the
data department, sending much smaller blocks of data than FTP, and there’s
no authentication as with FTP, so it’s insecure. Few sites support it because
of the inherent security risks.