LOL telnet = old... Start/Run/ Then type Telnet... there you go and as for how to us it ... www.google.com ... How to telnet maybe =P
Telnet is a standard Internet protocol for accessing remote systems and is used local area network (LAN) connections.
I would suggest you give some relevant titles to the thread you create and also should read the Before you make a query thread.
we use telnet for opening Router settings. to use it open windows command (Start>Run>cmd) then command will open write ( telnet defaultgate way) after that U will show (password:) write password of your router