The Basics of Computer Hardware

Computer hardware is the physical equipment that makes up a personal computer. It includes a computer case, central processing unit, random access memory, monitor and mouse.

Here is a picture of the flat “motherboard” (like 8.5 x 11 piece of paper) that the various components plug into. It shows the CPU held tightly against the motherboard with a copper “heatsink” that conducts heat away from the chip.


The motherboard provides a platform for installing the CPU, system memory and expansion slots. It also manages communication between the components. It has power connectors that deliver electricity from the power supply and front panel connectors to hook up the computer’s switches and indicator LEDs.

The CPU is a microprocessor that receives input from the user and tells the other parts of the computer what to do. The Motherboard’s memory slots hold RAM that acts as temporary storage for data and instructions.

Other ports on the Motherboard connect to a hard drive for storage, and a network card to allow you to access the Internet via a wired connection or wirelessly. The Motherboard also contains a cooling fan to eliminate excess heat generated by its components.


The processor, also known as the central processing unit or CPU, is a core part of most modern PCs and mobile devices. It interprets the program instructions from an operating system or other software and executes trillions of calculations to produce the output that a user will interact with.

The CPU is like the brain of a computer, telling other hardware components like your GPU or disk drives what to do. Choosing the right processor type depends on your needs: a quad-core CPU can handle most office and general computing tasks, while hexa-core CPUs are perfect for gaming and other heavy-duty tasks. A GPU is a specialized microprocessor that crunches numbers to create smooth graphics on your screen.


RAM is short-term memory that a computer uses to load software applications and user data. It’s volatile, meaning it loses its stored data when the computer shuts off.

As a hardware component, RAM is built from transistors and capacitors that store an electric charge and convert data bits into the physical form of a memory cell. The more RAM your PC has, the faster it will run.

Most modern computers use SDRAM – or synchronous dynamic random-access memory – which operates in synchronization with the CPU clock, improving performance. This type of RAM is often marketed with its speed in megatransfers per second (MT/s). It comes on rectangular chips packaged together onto a card that plugs into the motherboard socket known as a DIMM.

Graphics Card

The graphics card (GPU) renders images, video and 2D and 3D animations for display, freeing up the CPU to do other tasks. It’s also found in laptops, smartwatches and other devices with screens.

The GPU takes input from the CPU about what should appear on the screen, then rapidly updates its onboard memory to reflect those changes. That information then whizzes off to the monitor, where colors, lines, textures, lighting and shading appear.

Discrete cards slip into an expansion slot on the motherboard, while integrated chips are built onto the CPU. Dedicated graphics cards have a fan and heat sink to keep them cool, and they usually require their own power connector.

Sound Card

A sound card (or audio card) is an expansion board that facilitates input and output of audio signals to and from a computer under the control of software applications. A sound card converts digital signals into analog signals and vice versa.

Most modern computers have built-in sound cards. While these devices may be adequate for many casual computer users, most people prefer to use a superior third-party audio card.

A sound card has ports that connect to external speakers, microphones, and headphones. Some cards offer advanced features for audiophiles such as a front bay interface, MIDI support, and surround sound capabilities. Most cards also contain a digital to analog converter, which translates sound waves into the digital code that becomes an audio file.

Network Card

A network card enables your computer to connect to other computers on a local area network (LAN) or the Internet. Wired network cards are typically plugged into an Ethernet jack, while wireless NICs use radio waves to communicate with other devices on the same network.

The NIC implements the first two layers of the OSI model, which include the physical layer and data link layer. It also supports routable protocols that allow small groups of computers to exchange information over large networks.

Most computers come with a NIC preinstalled, and many online walkthroughs exist to help you install one if yours does not have it. You can also find external NICs for laptops or other devices that do not have an internal slot.