A computer system is composed of two parts namely computer hardware and computer software.

Computer software are programs that run the hardware. Therefore, without software, your computer will not function.

What is Computer Hardware

On the Computer, hardware refers to the physical components of the computer. These are computer parts that are tangible and we can see them. Below is a summary of computer hardware and their functions.

Examples of computer hardware include a central processing unit (CPU), mouse, monitor, keyboard, Random Access Memory (RAM), power unit, and hard disk among others.

We categorise the computer hardware into two broad categories. They include the basic/fundamental computer hardware and computer peripherals.

The 8 Basic/Fundamental Computer Hardware

These are computer hardware that a computer cannot function without. In other words, a computer requires this hardware to operate. The 7 Fundamental hardware include:

  1. Computer Case
  2. CPU
  3. Hard Drive
  4. Graphics Card
  5. MotherBoard
  6. RAM
  7. Power Supply Unit
  8. Cooling unit

Let’s see the function of each of these hardware components.

1. The Computer Case

A case is a computer house. It is a plastic or a metallic box that house the rest of the computer components.

The case is specially made to accommodate all other components including those connecting from outside.

Therefore, you will find the case with space to allow other components to connect. Other computer components are mounted to the case using screws.

2. Power Supply Unit (PSU)

A PSU provides computer components with electricity power. PSU converts AC current to DC current.

PSU is a combination of the AC to DC converter and the charging unit that we plug into the power sockets.

3. Motherboard

Motherboard Circuitry

A motherboard picture

The motherboard is the circuit board of a computer. It provides mounting to various components inside the computer case.

The  board enable different components to send electrical signals to one another depending on the instructions provided

Thus a motherboard holds various components together and enables them to communicate.

The main components of a motherboard include an integrated circuit (IC), transistors, diodes, connecting wires, and printed board.

4. CPU (Central Processing Unit)

Central Processing Unit (CPU)

Central Processing Unit

A CPU is a unit that processes instructions and controls data flow within the computer.

Therefore, all data and instructions you input in a computer are processed from in the CPU.

For this reason, a CPU is commonly referred to as the brain of the computer.

The CPU has three main components. They include the Arithmetic and Logic Unit, a control unit, and the Memory unit.

5. Computer Hard Drive

Computer Storage Device

Hard Drive Picture

The hard drive is the computer store. That’s why the hard drive is also commonly referred to as computer Storage.

All saved data including videos, pictures, documents, and music among others are stored here. Therefore, when you copy a movie from a friend you usually save it at the hard drive.

Common hard disk sizes in the market include 80GB, 120GB, 200GB, 500GB, and 1TB. It is advisable to buy a computer with a large hard drive space.

The hard drive can run out of space depending on how much you save in it. A common warning is a computer you are running low in your disk space.

If this happens, don’t panic. You can upgrade your hard drive say from 80 GB t0 500GB by buying and replacing a 500GB hard drive.

However, the hard drive is very slow in accessing the files and delivering them to the CPU for processing. Such is undesirable.

For instance, you cannot wish to wait for a minute for a word document to open. Or for two minutes for a movie to open. Obviously, it is undesirable.

It is for this reason that a computer has a Random Access Memory (RAM) discussed below.

6. Random Access Memory (RAM)

Random Access Memory (RAM)

Computer RAM

A RAM is a computer memory that temporarily stores data and instructions that are currently in use. RAM  commonly referred to as Memory.

The memory differs from the hard drive in that it is faster to access data.

Instead of computer accessing files every time like in hard drive, the CPU fetches the instructions and stores in the RAM.

Therefore, RAM helps the CPU to access files faster thus increasing the processing speed of a computer.

How does this happen? When you launch a program, the CPU identifies the files required to run the program in the hard drive.

The CPU then pulls these files from the Hard drive to the RAM. As we have said before, the CPU can then quickly access them from the RAM

This makes the program run faster termed as high processing speed. Therefore, the higher the RAM, the higher the processing speed.

However, RAM is a volatile memory. By this, it means whenever the power goes off, the memory is erased.

If you have a computer with a small RAM, you can upgrade your RAM say from 4GB to 8GB or 16GB to give your computer faster processing speeds.

7. Graphics Card and the Monitor

You have stored your video in the hard drive. You have the right RAM to quickly load it to the CPU for processing. Your motherboard can display the video in the screen

However, the video quality will not be very good. It is, for this reason, we have a Graphics card in computers.

A graphics card works in conjunction with the computer screen A graphics card simply determines the colour intensity of various parts of the picture or videos.

8. The Cooling System

Electronic Cooling Fan

Electronic Cooling Fan

Various computer components explained above emit heat while in operation. Also, various components in a computer can only operate within a specific temperature range

Therefore, if the temperature goes beyond the range your computer will switch off to protect the components.

To prevent such from occurring, computers have a cooling system. The cooling system is made of heat sink bars and a fan.

The bars conduct heat away from the components hence cooling their environment. Similarly, a fan constantly rotates to pump hot air away and cold air to the components.

The combination of the two ensures the internal temperature of the computer is conducive for components to operate optimally.

When you switch on your computer ahd it goes off after a minute or so. Most likely your fan has malfunctioned. The computer is turning off due to overheating

  Peripherals Computer Hardware

These are computer parts that a computer can function without. Such hardware components are meant to make a computer easier to use.

They include the input devices and output devices are the oldest peripheral hardware. However, technological advancement has seen the introduction of expansion cards.

Below is a comprehensive summary of the common peripheral hardware.

Input Devices

These are devices that we use to input data to the computer. Examples include keyboard, mouse, joystick, and touch screen. trackball, and touchpad among others.

Output Devices 

These are devices that present data out of the computer to the user. Examples include a microphone, headphones, or a speaker.

Computer Expansion Cards

A Bluetooth adapter is a USB device designed to receive and transmit Bluetooth signals wirelessly. The adapter is plugged to any USB ports in your computer. A good example is a network interface card.

Network Interface Card (NIC)

NIC is a hardware component that connects a computer to a network source. We usually connect our computer to the internet source through an RJ45 ethernet cable.

Are you aware that the port through which we plug the ethernet cable is part of the NIC? If not, now you know.

Different NIC cards support different internet speeds. Popular speeds include 10mbps, 100mbps, 1Gbps, up to a maximum of 160Gbps.