MAC ID

A Media Access Control address (MAC address) is a unique identifier allocated to network interfaces for communications on the physical network segment. MAC addresses are used for many network technologies and most IEEE 802 network technologies (including Ethernet). MAC addresses are used in the Media Access Control protocol sub-layer of the OSI reference model.
MAC addresses are most often assigned via the manufacturer of a network interface card (NIC) and are saved within its hardware, the card's read-only memory, or a number of else firmware mechanism.
A MAC address usually encodes the manufacturer's registered identification number.
MAC addresses - hardware addresses that uniquely identifies each node of a network.

In IEEE 802 networks, in the OSI Reference Model, Data Link Control (DLC) layer is divided into two sub-layers: the Logical Link Control (LLC) layer and the Media Access Control (MAC) layer.
The standard (IEEE 802) format of MAC-48 addresses in user-friendly form is six groups of two hex digits, separated by colons (:) or hyphens (-), e.g. e8:04:62:90:07:62, 00-1E-37-18-50-DB. Another pattern used by networking equipment (e.g. Cisco) uses three groups of four hexadecimal digits separated by dots (.), e.g. 0016.4d2e.7d10.
Technologies that use the MAC-48 format: 802.11 WiFi networks, Ethernet, Token Ring (IEEE 802.5), Bluetooth, other IEEE 802 networks, FDDI and many others.