I am writing a program about client-server. The problem is ,Do i need to connect two computers to test client's program and server's program ?

Thanks for reading my msg.

not really... What are the specifics, are you running a DB on off a web server?? What I do is a write the connection to the server as a variable. While developing on my machine, I point to my machine as the server (and client). When I put the software on other client machines, I make sure the connection variable to the server is change accordingly. Got it??