It is also known as a physical or hardware address. MAC Address or media access control address is a unique ID assigned to network interface cards (NICs). All this information is useful if you want to verify the generated mac address with the original vendor of this device in OUI vendor database. Finding the mac address from this database tells us which manufacturer originally manufactured this device and what is the prefix, postfix of a given mac address, moreover it tells us what country was this device manufactured. The MAC Address vendor database consists of a list of mac addresses of all devices manufactured till date. MAC Address Lookup Tool searches your MAC Address or OUI in mac address vendor database.