cocalol wrote:Through a port i can know if my other computer has an exploit i can use ?
Listening services may have a vulnerability. Not the ports themselves. You use a port scanner to see which ports are open and what, if any, services are listening for communications on that port. Knowing that application X version 1.23 may be running on, for example, port 25, gives you a good place to start researching for any known vulnerabilities with that particular application.