All network adapters have an unique identifier assigned by the manufacturer known as Media Access Control address (MAC address), this MAC address is used to identify a particular device on a network and was intended as a globally unique identification numbering system to trace network activity and implement restrictions and security, MAC address are used by many ISP's worldover for binding network access to a particular modem, however this MAC number can be changed easily via readily available noob friendly MAC spoofing tools, here are few tricks and tools to spoof your MAC address on Windows, Linux and Apple Mac.
Changing the MAC address on Windows is very easy, all you have to do is to use free MAC spoofing utilities like "Technitium MAC Address Changer", "SMAC" or "EtherChange".