Little Pool

Connection
Server : $nc -l(istening) -p(ort) 6789 -vv(verbose)
Client : $nc 'ipofserver' 6789

File Transfer
Server : $nc -l -vv -p 6789 >serverfilename
Client : $nc 'ipofserver' 6789 <clientfilename

client's file will be sent to Server

Telnet
Server: $nc -l -p 6789 -e(xec) /bin/bash         ::this will excute bash after connection
Client: $nc 'ipofserver' 6789

after that Client will be able to access server using bash