Chapter 2: Core Concepts of Computing

Introduction

Every special subject has its own words. Doctors, lawyers, and chefs all have a special vocabulary for their work. The world of technology is no different. Learning these common computer words is like learning a new language. It helps us all communicate clearly and understand technology better. This chapter will explain the most important concepts and terms in a simple way, so we can all speak the same tech language.

What is a Computer?

Fundamentally, a computer can be defined as an electronic device that operates under the control of instructions to process raw items and produce a useful result. To make this formal definition clear, let’s use a modern, everyday analogy that is very familiar: ordering an item from an online store like Shopee or Lazada.

Instructions

To perform any task, a computer needs a set of specific rules to follow. In computing, these rules are called instructions. The Shopee app, for example, is a program containing thousands of instructions that tell your phone exactly what to do at every step, such as how to display products, what to do when you click “Add to Cart,” and how to calculate the final price. A computer cannot think for itself; it is entirely dependent on these instructions.

Data

The raw details you provide to the computer are called data. When you use the Shopee app, the data you provide includes the product you select, the size and color you choose, and your shipping address. By themselves, these are just separate pieces of information. In the same way, computer data can be text, numbers, or images that are not yet organized into something meaningful.

Process

The action of the computer taking the raw data and following the instructions to work on it is called the process. When you click “Place Order,” the app begins processing. It takes the data you entered, communicates with Shopee’s servers to confirm the item is in stock, calculates the total cost including shipping, and prepares your order for the seller. This is the “work” being done behind the scenes.

Information

The final, organized result that the computer shows you is the information. The raw data has been transformed through the process into something that is now meaningful and useful to you. After the app has processed your order, it presents you with information: an order confirmation number, a summary of the items you purchased, the total price, and an estimated delivery date. This is a complete, organized answer to your action.

Store

Finally, after your order is complete, the details are saved in your account’s “Order History.” This is storage. The app saves the information about your purchase so that you can look at it again later, for example, to track your package or to request a return. A computer’s ability to save information for future use is one of its most important functions.

The Basic Cycle of Computing: IPOS

Every computer, from the most powerful server to the smartphone in your pocket, performs four fundamental operations to get any task done. We call this the IPOS cycle, which stands for Input, Process, Output, and Storage.

• Input: You provide data and instructions to the computer using an input device like a keyboard or mouse.
• Process: The computer’s brain, the CPU, works on the data according to the instructions.
• Output: The computer shows you the result (the information) on an output device like a screen.
• Storage: The computer saves the data or information for future use.

A Day-to-Day Example: Withdrawing Money from an ATM

The common task of withdrawing money from an Automated Teller Machine (ATM) serves as a practical illustration of the complete IPOS cycle. Although the transaction feels instantaneous to the user, the computer inside the ATM, in coordination with the bank’s central system, executes these four distinct steps in a precise order.

1. Input

This is the stage where you provide all the necessary data and instructions for the task. When you use an ATM, you are giving the computer multiple pieces of input.

• First Input (Data): You insert your bank card. The chip on your card contains data, specifically your account number, which the machine reads.
• Second Input (Data and Instruction): The screen asks for your PIN. When you type your secret number, you are providing more data. You are also giving the instruction to verify your identity.
• Third Input (Instruction): You select “Withdraw” from the menu on the screen. This is a clear instruction telling the computer what main task you want to perform.
• Fourth Input (Data): You enter the amount you wish to withdraw, for example, RM100. This is the final piece of data the computer needs.

At this point, you have given the computer all the raw materials it needs to begin its work.

2. Process

This is the “thinking” stage where the work happens behind the scenes. The ATM itself is a computer, but it needs to communicate with the bank’s main computer, which is a powerful server.

• The ATM takes all the input you provided (your account number, PIN, and the RM100 request) and sends it securely over a network to the bank’s central server.
• The server then processes this request. It follows a set of instructions to perform several checks. First, it verifies that the PIN you entered is the correct one for your account. Next, it checks your account balance to make sure you have enough money for the withdrawal.
• Once everything is confirmed, the server approves the transaction and sends an instruction back to the ATM, telling it that it is okay to give you the money. This complex verification and approval is the process.

3. Output

After the process is complete, the computer presents the results to you. This is the output, and it can happen in several forms at once.

• Physical Output: The ATM’s cash dispenser, which is a piece of hardware, receives the instruction from the process and gives you RM100 in cash.
• Printed Output: The machine’s printer produces a receipt. This receipt contains meaningful information, such as the amount you withdrew, the date and time, and your new account balance.
• Digital Output: The screen displays a message, such as “Transaction complete,” and may show your new balance. This is also information presented to you.

4. Storage

While the transaction at the ATM is now finished for you, the final and most important step for the bank is storage. This step ensures a permanent record of the event is created.

• The bank’s central server updates its main database. It permanently records that your account balance has been reduced by RM100. This is not a temporary change; it is the final, official record of the transaction. This ensures that if you check your balance from another ATM or on your phone’s banking app, it will show the correct, updated amount. This permanent recording of the result is the storage step.

Check Your Understanding: Q1