A Media Access Control (MAC) Address is a hardware identification number that is uniquely assigned to each device on a network. The MAC address is manufactured into every network card, such as an Ethernet card or Wi-Fi card, and therefore cannot be changed. Due to the extremely large amount of networkable devices in the world, each needs a unique MAC Address. MAC Addresses are made up of six two-digit hexadecimal numbers, separated by colons. Different vendors have been allocated blocks of MAC addresses such that you can visit a website with a MAC address to identify the vendor of a specific MAC address. MACVendor Lookup website
A MAC Address will look like: 00:0a:95:9d:38:16
Source: TechTerms
Related Reading: Don’t use MAC address Filtering on your WiFi Network
