Think of the command prompt on your windows box as your shell. You can run those commands from it. If you do, such as a ping the ping will originate from the box the ping command was sent from.

Now, if you use a shell account on another box (even though you're physically in front of your windows box), those ping packets will originate from the other box.

This is mainly a way to do stuff remotely. Skiddies and such use them for running exploits remotely, so as not to reveal their true location.