How Does a Computer Work? Best Beginner Level Guide (2023)

Introduction

Most of us own a computer or a smartphone. And most of you reading this post must have been curious about the working of the magical device in our home. How does a computer work? we all have heard computers can only understand 1s and 0s. but how do they let us watch videos, which are not clearly ones and zeroes? a computer is not built in a single moment with a single component. The magical result is due to the synchronized work of many components.

Familiarizing each component and realizing its role will help the user to both understand the complex machine as well as help user to solve simple software and hardware issues of your computer. One of the other fact that most people don’t realize is that the mobile phone each of us owns is also a computer. In other words, the computer is an electronic device that stores and processes data as per the instructions given by the user and give the result in time. So, without more introduction, let’s get to the basics of computers.

In this post, we will mainly look at the various hardware components and software components in a computer.

Types of Computer

Generally, computers can be categorized into four, such as Desktop computers, Laptop Computers, Smart Phones, and Super Computers. These divisions are based on size, power, and needed supporting peripheral devices. no one device or form factor can be called the perfect version, as all of the different models are made with different users in mind, and benefit different categories.

Desktop computer

This type of computer was developed in the 1970s and still continues on our tables. The first computer which can be considered a desktop was released in 1968 and is named Hewlett Packard 9100A. Desktop computers are meant to be fixed in a location. These computers come with separate parts like Monitor, Keyboard, CPU, Mouse, UPS, etc.

The machine runs with a continuous supply of AC. And a device called UPS(Uninterruptible Power Supply) is used to regulate the input voltage. The processor, Hard disk, RAM etc are inside a CPU case, and the other components are connected through wires, or via Bluetooth. PC computers are best if you always use them in a fixed location, as they give more performance and features for a given price.

Laptop Computer

Laptops are the most common type of computer that is used nowadays. It is portable, light, and easy to use. The invention of the laptop was revolutionary as it made life easier as we could carry a single brick wherever needed. All peripherals like monitor, keyboard, mouse, speakers, etc which were separate parts in a desktop computer are integrated into single brick. The first laptop computer Toshiba T1100 is designed in 1985.

The batteries inside the laptops are charged using the AC power source. Generally, the battery lasts for at least 4hrs hence no external connections are required for standard usage. The external devices if needed can be connected using different ports in the laptop. laptops are available across various form factors, ranging from as small as 12 inches to as large as 17 inches.

Smart Phones

This is the most used computer to date. The Smartphone which most people in the world own is a computer too. The average phone of this era is more powerful than the computers designed just a decade ago. Smartphones which substituted the role of many gadgets like clocks, calculators, calendars, cameras, etc is a portable computers with comparatively small output displays and less powerful processors than a computer.

Super Computers

They are the most powerful computer of the given time. Generally, Super Computers are not used for personal use. It is used by MNCs and other engineers who need to complete complex calculations in less time. Unlike other computers, the Super Computer can have more than one CPU (Central Processing Unit). This enables parallel processing thereby facilitating higher efficiency.

Main components of a Computer

As told earlier Computer is a machine that processes calculations needed by the user and gives the result back. The computer is not just a single object, all the power comes with the combined effort of many parts. A computer contains a processor which deals with the processing power, RAM(Random Access Memory) which stores the data that which processor needs soon, Display which is the primary medium of output, Secondary storage devices like HDD and SSD which stores the enormous data we store, Keyboard, Mouse, etc.

Processor

A processor or microprocessor deals with all the calculations inside the computer. Sometimes people call the processor CPU which is just partially correct as the processor of a device is not just a CPU but GPU (Graphics Processing Unit), and a lot of other components too. Modern processors are complex structure, that acts as the brain of your computer. it includes general processing units like CPU and GPU, as well as dedicated structures like ISP, MLU, encoders, and decoders for various formats, etc.

ALU

ALU which stands for Arithmetic Logic Unit is one of the important parts of the Central Processing Unit. ALU is responsible for all arithmetic and logic calculations. Examples of arithmetic operations in the basic levels are addition, subtraction, etc and logic operations are Logical AND, OR, XOR, NAND, bitwise operations, etc. As we already know all the processes inside a computer are done in the form of binary numbers which are 1 and 0. So all the above calculations are done in binary form.

CU

CU which is Control Unit is another important part of a processor. It controls and monitors all the functions by generating a timing signal which controls the flow of data between the processor, memory, and I/O devices. CU can be considered as the nervous system of a computer, which sent signals, and controls and coordinates the various processes of the computer.

Registers and Cache

It is a storage element within the processor that is exceptionally fast but the amount of storage is very less. Hence only data that the processor needs in a short time is stored. Apart from temporary registers, there are some registers with special functions like Program counter, Accumulator, Address register, etc. Caches are data storage devices that are larger than registers, but comparatively slower too. they are both used in combination to decrease the time between the request and service of data from and to the processor.

System Bus

It is responsible for communication between the parts of the computer. There are three busses called Address Bus, Data Bus, and Control Bus. as well as peripheral BUSes which connect the CPU to different Peripherals like RAM, HDD, SSD and GPU. PCIe, SATA etc are different standards used for communication through these Busses.

RAM

RAM which stands for Random Access memory is a primary memory that is used to store data and address that which processor might need soon. It is slower than registers within the processor but it is also cheaper and has more storage capacity than registers. RAM is volatile ie the data stored inside it vanish completely once the power of the computer goes off. The currently running application, operating system etc are stored inside the rum when the computer is running.

There is a widespread myth among us that the more the RAM better the performance of your device, but it is only partially correct. Your device will suffer for sure if you do heavy tasks and you have too little RAM. But it doesn’t mean that a normal smartphone user needs 8GB of RAM. To know how much RAM a Smartphone needs in 2023 click here.

Secondary Storage Devices

The volatility of the primary storage is overcome by the Secondary storage devices which most of us would be familiar with. The history of secondary storage devices ranges from the Magnetic tape of the late 1920s to SSDs. The prime advantage of the same over primary memory is its involatile nature. In addition, it offers huge storage space for less cost.

The major two types of secondary storage devices which we use in our computers nowadays are HDD (Hard Disk Drive) and SSD (Solid State Drives)(These are not applicable to mobile phones). SSDs are costlier than HDDs of the same capacity as it is faster. HDDs read and write data in the traditional way by moving its arm across the surface on the other hand SSDs have no moving part and hence make it faster.

By using SSD the bootup time of the OS and the waiting time for bulkier apps will reduce drastically. In many cases, the slowness of old laptops or Computers could be reduced by substituting HDD with SSD. For mobiles, the secondary storage devices are modifications of ROM flash chips, and perform better than HDD, but not as well as SSD.

Display

The display is the primary output device of a computer. The displays can be of many types. Out of many, the two seen around us are LCD and AMOLED. LCD which stands for Liquid Crystal Display is cheaper than AMOLED which stands for Active-Matrix Organic Light-Emitting Diodes. If compared LCDs are cheaper, bright, and more durable with great viewing angles but can’t achieve deep blacks, it is not flexible, and since it needs a backlight behind them the LCD screens are thicker. Amoled is better in quality, as it can produce inky blacks.

Peripherals

The parts of the computer through which instructions are given to the computer are known as Input devices and the parts through which the results are shown to the user are called Output devices. For understanding, the input devices of normal desktop computers are a keyboard, mouse, microphones, etc and the output devices are monitors, printers, etc.

Types of Software

Till now we spoke about various hardware of the computer. All the hardware is just a piece of plastic unless software or a set of instructions, programs, or procedures is run in it. A computer as we know it is a mix of both hardware and software, however great the hardware is, without proper software, the full experience cannot be achieved from a computer.

Operating Systems

It is the software that runs first when the computer is turned on. It acts as an interface between a user and computer hardware. It is the most important software and handles all the other software and hardware of the computer. It does basic tasks like memory management, process management, handling I/O operations also handles peripheral devices. The most used operating system is Android and other examples are Windows, ios, Linux, mac, etc. What types of software that is supported in the device, the features, etc are decided by the operating system for the most part.

System Software

These are the inbuilt applications that come preinstalled on your device. most operating systems have a number of such applications so that the OS is ready to use for most users out of the box. Some of the most known examples of system software are phone, messages, settings apps on your mobile phone, and task manager, paint, etc on your desktop.

User Software

Almost all modern operating systems allow us to install software that is not created by the creator itself. these apps are called third-party software, or simply User software. it is a very important part, as no operating system can provide all the different types of software required by every possible user. therefore, while OS contains a number of must-have apps, there will be third-party developers creating applications of different types to satisfy the needs of different users. Whatsapp, Facebook, Instagram, games, photoshop, etc are all examples of user software.

How does a computer understand human language?

Now that we know the basic hardware and software components of a computer, let us try to get a greatly simplified idea of how a computer works. For this, first, we should know how computers store, read and manipulate data, with the help of Just strings of Zeroes and Ones. Then, we can look at how your OS is loaded into the computer when the power is turned on.

Binary/Machine Language

As we have stated many times in this post, a computer only understands two states, ON and OFF, which are denoted by 1 and 0 respectively. in order to use the computer for any meaningful purpose, we should be able to at least use all the commonly used letters and alphabets of Human Languages. this is achieved by using a number system called Binary number system ( BASE 2), and the code that is purely made using ) and 1 is known as machine Language or Machine code.

In order to represent letters of our alphabet, we denote different letters using different numbers. For example, ASCII code uses 65 in binary as the equivalent of the letter ‘A’, 66 for ‘B’, and so on. a complete table of the ASCII code is given below, for a better understanding. In the simplest form, we can assume that the letters, words, images, and other things we see on the computer are just different permutations and combinations of these 0s and 1s.

Summary

The computer is an amazing creation, and probably the best creation of humankind. even though the full working of the computer is much more complex for most of us to comprehend, or even understand. But it is a very good idea to have a basic understanding of how this magic actually works, as it has become an indisputable part of our daily life. Hope you like this brief introduction to the working of a computer. If you want to more in-depth, kindly stay subscribed, are we are working on an intermediate level, which will be ready in the very near future.