What Is Computer Hardware?

pc hardware

Computer hardware encompasses the physical components that make up a desktop PC or laptop. It includes everything from the motherboard to the CPU. Without it, your computer wouldn’t be able to run the essential software programs that you use.

A hard disk drive is a data storage device that stores digitally encoded information on rapidly rotating platters with magnetic surfaces. Virtually every modern computer has a hard disk drive.


The motherboard is the main PCB on which other modular components like the CPU and RAM are installed. It also provides various expansion slots to install other devices / interfaces. Motherboards come in three popular sizes – ATX, Micro-ATX and Mini-ITX.

A typical motherboard has two key voltage regulation systems. The first is made up of metal-oxide semiconductor field-effect transistors (MOSFET) that are recognizable as flat rectangular components normally located around the CPU socket. The second is made up of chokes which sit beside the MOSFET to stabilize currents and provide resistance if there’s a sudden voltage spike. Motherboards also have power connections that connect to a computer’s power supply and distribute electricity optimally.


The CPU (central processing unit) is the brain of your computer. It interprets instructions while you’re surfing the web, creating documents, or running software programs.

The processor has two primary functional units: the arithmetic logic unit ALU and control unit CU. The arithmetic logic unit performs mathematical, logical, and decision operations. The control unit directs the operation of other components like memory and output devices.

The CPU works at such high speeds that it generates considerable heat, so it arrives with a metal heat sink and small fan that’s mounted on top of it. As technology progresses, CPUs have been doubling in processing power every two years as predicted by Moore’s law.

Graphics Card

Graphics cards are responsible for rendering the images you see on your screen, be it a game, video, document, or even your regular desktop environment. They do this by processing information sent to them from the CPU and whizzing it through onboard memory (called VRAM) to your monitor.

Graphic card technology continues to evolve at a breakneck pace. Today’s GPUs can render incredibly realistic games that are closer to reality than ever before.

It’s important to consider your gaming needs when choosing a graphics card. Most modern cards will have a recommended power supply size in watts on their box, and it’s best to match this with the size of your case and motherboard to ensure adequate cooling for optimum performance.


A hardware component that is responsible for storing on-the-fly information created by computer programs and making it available to the CPU. This information could be in the form of rendered images for graphic design or edited video, or it might be a word-processing document.

Primary memory is able to communicate with the CPU at lightning-fast speeds, but it’s volatile and loses data when power is removed. It includes RAM and ROM. Secondary storage is non-volatile and able to store data long-term. It’s found in a variety of electro-mechanical forms like hard disk drives, solid-state drives and tape. It is typically more affordable and available in much larger capacity than primary storage.

Hard Drive

A hard drive stores permanent and temporary data, such as programs, operating systems, device files and photos. It requires moving parts — spinning disks and a mechanical head to read and write data — which can cause them to fail after prolonged usage.

A DSP in the drive electronics takes the raw analog voltages from the read/write head and decodes them into standard interface data. That DSP also performs bad sector remapping and gathers information for S.M.A.R.T (Self-Monitoring, Analysis and Reporting Technology).

Modern HDDs use a single data/control cable, a significant improvement over older IDE/ATA drives that used separate cables for each. This reduces the risk of data loss due to unreliable connections.

Power Supply

A Power Supply is the heart of any computer and is the point where power enters and is allocated by the motherboard to individual hardware components. Without the right wattage PSU your computer will not function correctly and may not even start up.

The PSU should be well calculated and able to support the specific voltage requirements of different system components (motherboard, CPU, hard disk etc). It should also physically fit in the computer cabinet form factor and come with suitable connectors to accommodate the various components and their different voltage and current needs. A PSU consists of several components including connectors, switches and rectifier which converts AC to DC.