You may have noticed that every piece of hardware on your local network has a MAC address in addition to the IP address. Except for switches which have switch MAC address, all devices that connected to the Internet have this unique identifying number, from desktop computers, laptops, cell phones, tablets to wireless security cameras, and even your connected refrigerator have a MAC address. So, why does your network devices need two addresses to connect to a network? Isn’t an IP address sufficient? What exactly is that MAC address for?