Want to know if someone is hacking your computer? Command Prompt can help you find if someone you don't know is connected to your computer stealing private data. Just execute netstat -a and the command prompt will return a list of computers that your computer is connected to. In the results returned, Proto column gives the type of data transmission taking place (TCP or UDP) , Local address column gives the port with which your computer is connected to an external computer and the Foreign Address column gives the external computer you are connected to along with the port being used for the connection. State gives the state of the connection (whether a connection is actually established, or waiting for transmission or is “Timed Out”).