There are many reasons why you might want to change the name of your computer becasue the computer shows up in various lists around the network, and it's often nice to know which computer you're talking about.
Changing the name of the computer is luckily pretty easy. On a Windows computer just look at the properties of your computer. Then there's an option to change settings. Once you're looking at the settings, find the computer name and change it and Save it.
Then you'll be forced to reboot your computer to make the name change active. Once you do that you should be able to go back and look at the list of computers on your network. As an example on your network router and you'll see the correct name for your computer making it far easier to determine which computer is which on your network.