The telnet command is used for interactive communication with another host using the TELNET protocol.

For the purpose of remote login, the present client executable should be depreciated in favour of an ssh-client, or in some cases with variants like telnet-ssl or Kerberized TELNET clients. The most important reason is that this implementation exchanges user name and password in clear text.

On the other hand, the present program does satisfy common use cases of network diagnostics, like protocol testing of SMTP services, so it can become handy enough.