What is an Ethernet Card?

The system that helps connect a computer to an Ethernet network is called an Ethernet card. Another name for such a card is Network Interface Card (NIC). It can be inserted into one of the slots provided on the motherboard of the computer. Each of these cards has a unique identification number, known as the MAC address. Ever since their inception by the Xerox Company, Ethernet cards have managed to find their way into nearly every single computer in the world Source: http://www.tech-faq.com/ethernet-card.shtml#