The Basics of Computer Hardware

pc hardware

Computer hardware is the physical parts that make up your system. It consists of components like the central processing unit, random access memory, motherboard and data storage devices. It also includes external devices like monitors and keyboards.

The motherboard connects all the other hardware in your system. It has slots for RAM, a socket for the processor, and usually a slot for a graphics card.


A processor is the brain behind your computer, performing trillions of calculations per second to make the hardware work. It interprets the digital instructions that come from software programs or operating systems.

It performs arithmetic, logical, input/output (I/O) and other basic operations. It also stores and processes the data used by other devices, including hard drives.

It has an Arithmetic Logic Unit that performs math and logical functions, while the Control Unit handles all the CPU’s operations. It also includes L1 and L2 memory caches that enable it to process information faster. Some CPUs are single-core, while others have multiple cores that can multitask – depending on your needs and budget.


The memory holds your computer’s programs and user data. Its primary form is volatile RAM (random access memory) that makes information immediately accessible to programs; stored data clears when the computer shuts off.

Cache is a type of super-fast RAM built into the CPU that reduces the time it takes to transfer data into and out of standard RAM. A CPU’s speed — measured in megahertz and gigahertz — determines how quickly it can process instructions.

A CPU fits into a socket on a flat “motherboard”, smaller than an 8.5″ x 11″ piece of paper. It is covered with a copper “heat sink” that presses tightly against the chip, conducting heat away to its (not shown) thermal paste cover.

Graphics Card

A graphics card is responsible for handling the graphical workload that software generates on your computer. It turns binary data into pixels (tiny squares that combine to make the images we see on our monitors and displays) and rasterizes them, adding lighting, texture and color.

The GPU breaks up this work into thousands of parallel tasks that it can execute much more quickly than the CPU could. It also holds completed images in memory, called video RAM. Graphics cards can be integrated into the motherboard or added as an expansion card. A fast graphics card can have as much as 8GB of VRAM.

Hard Drive

The hard drive stores information like apps and documents on physical discs that your computer reads with an arm that travels across them (similarly to how a record player works). However, there’s also a newer generation of storage called the solid-state drive, which is faster and more reliable.

The CPU and motherboard use software to tell what’s known as the “read/write head” where to go on the platters. Each platter has thousands of subdivisions that can accept an electric charge — the magnetic field’s binary translation of these charges into 1s and 0s forms digital data. This data can give the CPU instructions, such as updating your operating system or opening a saved document.

Sound Card

Most computers have a built-in sound card, but for gaming or other advanced purposes, a dedicated one can provide much better performance and quality. A rectangular piece of hardware with a lot of connections on its sides, a typical sound card has analog to digital converters that convert audio file code into electrical impulses that the speakers can turn into physical sound waves.

From the beeps and boops of early PCs to full orchestral soundtracks in modern games, the sound card has come a long way. Like other computer hardware, sound cards are usually powered by device drivers, low-level programs that connect the physical hardware to the operating system.

Network Card

The network card (also called NIC) is the most important hardware component in your computer to ensure a reliable Internet connection. It converts any data sent to the Internet into high and low electrical pulses on Ethernet or wireless media.

It also translates the protocol layers of OSI model into a physical format that your computer can understand. Most computers have a working network card built into the motherboard directly these days. However if yours isn’t then you can add one to it easily. Upgrading to a newer card is recommended if you encounter frequent dropouts or poor signal quality. You can also look at Gigabit cards for faster connections.