Pre-CSS 1

What is an integrated setup of hardware and software working together to process data and produce output?

Computer System

Four essential functions of a computer system:

• Input – Receive data (keyboard, mouse, microphone)

• Process – Manipulate data (CPU, RAM)

• Storage – Save data (HDD, SSD, flash drive)

• Output – Present data (monitor, printer, speaker)

Internal Hardware Components of a Computer:

1. Motherboard

2. CPU (Central Processing Unit)

3. RAM (Random Access Memory)

4. HDD/SSD (Hard Drive/Solid State Drive)

5. PSU (Power Supply Unit)

6. Cooling System

7. CMOS Battery

8. Expansion Cards (GPU, Network Card, Sound Card)

Main circuit board. Connects all components together.

Motherboard

The brain of the computer. Executes instructions.

CPU (Central Processing Unit)

Temporary memory used during processing. Volatile.

RAM (Random Access Memory)

Stores data permanently. SSD is faster and more durable.

HDD/SSD (Hard Drive/Solid State Drive)

Converts AC electricity into DC power usable by components.

PSU (Power Supply Unit)

Prevents overheating using fans or heat sinks.

Cooling System

Powers the BIOS chip to retain system settings.

CMOS Battery

Enhance graphics, internet connectivity, or sound processing.

Expansion Cards (GPU, Network Card, Sound Card)

External Hardware Components of a Computer:

1. Input

2. Output

3. I/O (Both)

Input Devices:

1. Keyboard

2. Mouse

3. Scanner

4. Microphone

Output Devices:

1. Monitor

2. Printer

3. Speaker

Input/Output (I/O) Devices:

1. Touchscreen monitors

2. Headset

3. USB Flash drive

Ports and Connectors:

1. USB

2. HDMI

3. Ethernet (RJ-45)

4. Audio Jack (3.5mm)

5. VGA/DVI

Universal connection for devices

USB

Audio and video output

HDMI

Wired internet connection

Ethernet (RJ-45)

Input/output for sound

Audio Jack (3.5mm)

Video display (older monitors)

VGA/DVI

Basic Computer FIrmware:

1. BIOS

2. UEFI

• Stored on the motherboard’s ROM chip

• Controls hardware settings like boot order

• Can be accessed using keys like DEL, F2, F10 during startup

BIOS (Basic Input/Output System)

• A modern version of BIOS

• Mouse-compatible, graphical, faster booting

• Supports drives over 2TB and secure booting

UEFI (Unified Extensible Firmware Interface)

The Booting Process (Simple Version):

1. Power is supplied to the system

2. BIOS/UEFI runs POST (Power-On Self Test)

3. BIOS checks for bootable devices

4. OS is loaded from drive (e.g., Windows boots)

5. Computer becomes operational

Types of Storage Devices

1. Magnetic

2. Solid-State

3. Optical

4. Flash

Magnetic Storage Device:

1. HDD

2. Medium speed

3. 3-5 years lifespan

Solid-State Storage Device:

1. SSD, NVMe

2. Very fast speed

3. 5-10 years lifespan

Optical Storage Device:

1. CD, DVD

2. Slow speed

3. 3-7 years lifespan

Flash Storage Device:

1. USB Drive

2. Fast speed

3. 3-10 years lifespan

Types of Computers (Basic Classification):

1. Desktop PC

2. Laptop

3. Server

4. Embedded System

5. Mobile Devices

Stationary, customizable, serviceable

Desktop PC

Portable, all-in-one, less customizable

Laptop

High-power system for hosting services or data

Server

Found in smart devices (e.g., ATM, microwave)

Embedded System

Tablets, phones; simplified computers

Mobile Devices