What is a MAC Address?
A MAC address or Media Access Control address is a 48-bit or 64-bit address that associated with a network adaptor. While IP addresses are associated to software, MAC addresses are associated to hardware of network adaptors. That is why sometimes, MAC address is called, hardware address, burned-in address (BIA), or physical address.
MAC address shows in hexadecimal format. In 48-bit address format is, for example, 01-23-45-67-89-AB. In 64-bit address format is, for example, 01-23-45-67-89-AB-CD-EF. Sometimes, colons (:) are used instead of dashes (-).
MAC address is often permanent, but in some cases, it can be changed.
There are two types of MAC addresses:
1) Universally Administered Address (UAA) is mostly used type of MAC address. It is assigned address to network adaptor when it is manufactured.
2) Locally Administered Address (LAA) is type of MAC address that can change its address.
It is best practice to use UAA instead of assigning LAA, if there is no good reason to do so. MAC addresses are designed for security purpose, because they are rarely changed.