System Software

ITEC 101: Introduction to Information Technology

Mr. Seng Theara

Learning Outcome

Distinguish system software from application software.
Explain how an operating system manages hardware, applications, files, and memory.
Demonstrate multitasking and monitor computer resources.
Compare operating systems and graphical versus command-line interfaces.
Use built-in utility programs for file management, compression, cleanup, backup, and security.
Recommend appropriate operating systems and utility tools for real-world situations

System Software

Imagine you buy a brand-new laptop. It has an Intel Core i7, 16 GB RAM, and a 512 GB SSD. Everything is working perfectly. But there is one problem: it has no Windows, Linux, or any other operating system installed. What happens when you turn it on?

Can the computer still power on without an operating system?

1. Yes, firmware can still start

2. No, it cannot receive electricity

3. Only if the SSD is removed

Can the computer still power on without an operating system?

1. Yes, firmware can still start

2. No, it cannot receive electricity

3. Only if the SSD is removed

Can the computer still power on without an operating system?

1. Yes, firmware can still start

2. No, it cannot receive electricity

3. Only if the SSD is removed

Can you normally browse files on the SSD without an operating system?

1. Yes, just double-click the SSD

2. No, normal file browsing requires software such as an OS

3. All files disappear

Can the computer still power on without an operating system?

1. Yes, firmware can still start

2. No, it cannot receive electricity

3. Only if the SSD is removed

Can you normally browse files on the SSD without an operating system?

1. Yes, just double-click the SSD

2. No, normal file browsing requires software such as an OS

3. All files disappear

What can and cannot work?

Function Without an installed OS

Power on the computer
Enter BIOS/UEFI settings
Detect CPU, RAM, and SSD
Open Microsoft Word normally
Run Chrome normally
Browse files using File Explorer
Install an operating system

What can and cannot work?

Function Without an installed OS

Power on the computer	Yes
Enter BIOS/UEFI settings	yes
Detect CPU, RAM, and SSD	yes, through firmware
Open Microsoft Word normally	No
Run Chrome normally	No
Browse files using File Explorer	No
Install an operating system	Yes, using bootable installation media

BIOS/UEFI Setup

Opens the firmware settings, where you can inspect or configure hardware-related options such as:

CPU, RAM, and storage information
Boot order
Secure Boot
System date and time
Virtualization settings

BIOS/UEFI Setup

Opens the firmware settings, where you can inspect or configure hardware-related options such as:

CPU, RAM, and storage information
Boot order
Secure Boot
System date and time
Virtualization settings

Often F2, F10, Delete, or Esc, depending on the laptop

Boot Menu

Opens a menu to select which device to start from, such as:

Internal SSD / Windows Boot Manager
Bootable USB flash drive

Boot Menu

Opens a menu to select which device to start from, such as:

Internal SSD / Windows Boot Manager
Bootable USB flash drive

For example, when installing Windows from a USB drive, you can select that USB drive from the Boot Menu.

Boot Menu

Opens a menu to select which device to start from, such as:

Internal SSD / Windows Boot Manager
Bootable USB flash drive

For example, when installing Windows from a USB drive, you can select that USB drive from the Boot Menu.

Often F12, F9, F11, or Esc, depending on the laptop.

When you press the power button, how does your computer know where Windows is and how to start it?

Computer starts powering on

Power Button

BIOS/UEFI

Bootloader

Initializes and checks hardware, finds a boot device

Starts loading Windows from the SSD

OS Kernel

Login Screen

Initializes essential system services and manages resources

Computer is ready for you to sign in and use

OS Kernel

The operating system (OS) kernel is the core software component that acts as the primary interface between a computer's physical hardware and its running applications.

Investigate Using Task Manager

A computer can keep multiple programs running or ready to run. The operating system manages these programs and schedules their work on the CPU.

Investigate Using Task Manager

A computer can keep multiple programs running or ready to run. The operating system manages these programs and schedules their work on the CPU.

Column Meaning

CPU	How much CPU processing a program is using
Memory	How much RAM a program occupies
Disk	How actively a program reads or writes storage
Network	How much data a program transfers over the network

Multitasking, Multiprocessing, Multithreading

Multitasking

The ability of an operating system to have more than one program (task) open at one time

The ability or attempt to perform, operate, or handle more than one task, job, or program at the exact same time

Multiprocessing

Multiple processors (or multiple cores) are used in one computer system to perform work more efficiently

Chrome Process

Powerpoint Process

CPU Core 1

CPU Core 2

Multiprocessing

Multiple processors (or multiple cores) are used in one computer system to perform work more efficiently

Chrome Process

Powerpoint Process

CPU Core 1

CPU Core 2

Imagine several separate kitchens preparing different orders, each with its own equipment and workspace.

Multithreading

Multithreading means a single process can have multiple threads of execution. These threads share the process's memory and resources.

Thread 1

Game logic

Thread 2

Physics calculations

Thread 3

Audio processing

Thread 4

Background loading

Multithreading

Multithreading means a single process can have multiple threads of execution. These threads share the process's memory and resources.

Imagine a team working on different parts of the same meal: one prepares ingredients, another cooks, and another plates the food.

Thread 1

Game logic

Thread 2

Physics calculations

Thread 3

Audio processing

Thread 4

Background loading

Core vs Thread

GUI vs. CLI

GUI-Graphical User Interface

Uses windows, icons, and menus
Controlled using mouse and keyboard

CLI- Command-Line Interface

Uses text commands
Controlled mainly using keyboard

CLI Command

Command What does it do?

`cd`	Change folder
`cd ..`	Go to the parent folder
`mkdir`	Create a folder
`dir`	Display files and folders
`tree /f`	Display folder structure and files
`echo`	Display text or write to a file
`copy`	Copy a file

`ren`	Rename a file or folder
`move`	Move a file
`type`	Read a text file
`del`	Delete a file
`rmdir`	Delete an empty folder
`cls`	Clear the terminal screen
`help`	List available CMD commands

Command What does it do?

Practice

Part A - Create your folders

Go to your Desktop using CMD.
Create a folder named University.
Inside University, create two folders: ITEC101 and Python.
Inside ITEC101, create two folders: Assignments and Projects.
Display the complete folder structure.

Part B - Create and edit files

Create a file named student.txt inside ITEC101 containing your name.
Display the contents of student.txt in CMD.
Add the text "Welcome to ITEC101" without removing the existing text.
Open student.txt using Notepad.
Create a file named homework.txt inside Assignments.

Part C - Manage your files

Copy student.txt into Projects.
Rename the copied file to profile.txt.
Move homework.txt from Assignments to Projects.
Display all files inside Projects.
Delete homework.txt from Projects.
Display the final folder structure, including files.

Discussion