This article will mainly introduce what a network card is? This article will contain the answer to this question.
Definition
Computer hardware designers create pieces of hardware to enable computers to communicate on a network. It is positioned between the OSI model's first and second layers due to its possession of a MAC address. It facilitates user connectivity via wired or wireless means.
Each network card has a unique 48-bit serial number, referred to as a MAC address, stored in its ROM. It's essential for every computer within the network to have a unique MAC address.
Every produced network card has a unique address. The Institute of Electrical and Electronics Engineers assigns different MAC addresses to makers of network interface controllers.

Introduction
It has a processor and memory (including RAM and ROM) installed on it. It communicates with the local area network using cables or twisted pairs in serial transmission.
The device communicates with the computer at the same time through the I/O bus on the motherboard.
Therefore, one of its important functions is to perform serial/parallel conversion. The network and computer bus operate at different data rates, so a memory chip must store data temporarily.
It was formerly connected to the computer bus as an add-on card. Most new computers have a built-in network interface because Ethernet is widely used and affordable.
Certain motherboards come with pre-installed Ethernet, while others have an inexpensive network card attached to the motherboard.
The connection is made through either PCI or PCI-Express. A separate network card is unnecessary unless multiple interfaces or diverse network types are required. Even more recent motherboards might come with built-in dual network (Ethernet) interfaces.
To install a network card, you need to add the right driver to your computer's operating system. Additionally, the network card must possess the ability to carry out the Ethernet protocol.
It relies on the computer's power source and the computer controls it because it doesn't have its own power source. Hence, it can be considered as a partially independent entity. Upon receiving a faulty frame, it disposes of the frame.
When the device receives a correct frame, it sends an interrupt to the computer. The frame is then transmitted to the network layer within the protocol stack.
The system dispatches an IP data packet. The network card puts the packet into a frame. The network card sends the frame to the local network.
As integration continually improves, the quantity of chips on the network card is consistently reducing. Despite the variety of network cards produced by different manufacturers, their functionalities remain comparable.
The above is an introduction to what a network card is.