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,Chapter 1: Introduction to Computers
1.1 Types of Computers
Type Description
Server Computer used to provide services to other computers
Workstation Computer intended for individual use; faster than a normal
computer
PC / Desktop Compact computer with a complete system
Embedded Systems / Device that performs specific tasks
Dedicated Devices
What is a computer?
A computer processes data through four stages:
• Input: Data that a user enters
• Processing: The CPU works with the data to process it, through memory
• Storage: Saved data on the computer
• Output: Processed information is shown to the user through screens and sound
GUI (Graphical User Interface): Allows the user to communicate with the computer
NB: Exams will refer to 'computing devices' increasingly.
Additional Computer Types
Type Description Typical Specifications
Personal / Home Performs a wide range of tasks; Entry level CPU and RAM;
cheap to buy; uses basic input and Mouse/Keyboard;
output devices Monitor/Printer; Modem
Enterprise Used by companies with many users Higher CPU and RAM
across the country; uses a large speed; Keyboard/barcode
network to connect scanner; Network HDD;
Router
Why Use Computers?
• Computers improve productivity
• GIGO (Garbage In, Garbage Out): Inaccurate input provides an inaccurate result
• Data validation: Computers allow users to enter data more efficiently and accurately using
input masks and validation rules
• Computers are efficient
• Computers are accurate
• Computers are reliable
Saving Time (Efficiency)
• Fast shopping, banking, navigation
Communication Costs
• Video calls and file sharing are much cheaper than travelling
Efficiency
• Computers store and process data quickly
1
,Saving Labour
• Automation and robots complete tasks quicker
Accuracy and Reliability
• Computers perform tasks consistently with fewer errors
Effects on Time and Distance
• Instant communication across the world
Saving Paper
• Digital documents and online communication reduce paper use
Global Communication
• Networks and the internet enable social media
1.2 Data, Information, Knowledge, and Wisdom
Term Definition
Data Raw, unorganised facts that lack meaning on their own
Information Data that has been processed and organised to give it meaning
Knowledge Understanding gained from information; applying information to make
decisions
Wisdom Using knowledge and experience to make sound judgements and
decisions
1.3 Convergence
• It combines multiple technologies in one device
• Example: Smartphone
1.4 Social Implication and Environmental Impact
• Social connection is enhanced by computers
• Computers contribute to environmental issues such as high electricity use
Green Computing:
Reducing environmental impact through energy-efficient designs and biodegradable materials.
2
, Chapter 2: Hardware
Summary of Hardware
Component Type Purpose
INPUT DEVICES
Keyboard Standard / Laptop / Gaming / Enters information (letters) into
Virtual the computer
Pointing Device Mouse / Touchscreen / Controls movement of cursor on
Touchpad / Trackball screen
Scanning and Scanners / RFID / OCR Scans documents and converts
Reading Devices them to digital format
Video Devices Video Camera / Webcam Captures media and videos
Audio Devices Microphone / Voice Logger Communicates with computer
using a voice
Biometric Devices Fingerprint Scanner / Facial Measures a person's unique
Recognition characteristics
Point of Sale - Keeps track of retail stock and
prices
PROCESSING DEVICES
Motherboard - Connects all components
CPU - General processing of computer
GPU - Graphic processing
RAM - High speed, temporary storage
ROM - Information stored to turn
computer on
STORAGE DEVICES
Hard Disk Drive HDD (Internal / External) Slow, long-term storage
Solid State Drive SSD Fast, long-term storage
Flash Disk - Small, permanent storage device
(plug in)
Memory Cards - Permanent storage device for
digital information
CD / DVD / Blu-ray - Portable storage devices: data
can be copied
OUTPUT DEVICES
Display Devices LCD Monitor / TV Monitor / Displays images generated by
Projector computer
Printers Inkjet / Laser Converting soft copy to hard copy
3
,Chapter 1: Introduction to Computers
1.1 Types of Computers
Type Description
Server Computer used to provide services to other computers
Workstation Computer intended for individual use; faster than a normal
computer
PC / Desktop Compact computer with a complete system
Embedded Systems / Device that performs specific tasks
Dedicated Devices
What is a computer?
A computer processes data through four stages:
• Input: Data that a user enters
• Processing: The CPU works with the data to process it, through memory
• Storage: Saved data on the computer
• Output: Processed information is shown to the user through screens and sound
GUI (Graphical User Interface): Allows the user to communicate with the computer
NB: Exams will refer to 'computing devices' increasingly.
Additional Computer Types
Type Description Typical Specifications
Personal / Home Performs a wide range of tasks; Entry level CPU and RAM;
cheap to buy; uses basic input and Mouse/Keyboard;
output devices Monitor/Printer; Modem
Enterprise Used by companies with many users Higher CPU and RAM
across the country; uses a large speed; Keyboard/barcode
network to connect scanner; Network HDD;
Router
Why Use Computers?
• Computers improve productivity
• GIGO (Garbage In, Garbage Out): Inaccurate input provides an inaccurate result
• Data validation: Computers allow users to enter data more efficiently and accurately using
input masks and validation rules
• Computers are efficient
• Computers are accurate
• Computers are reliable
Saving Time (Efficiency)
• Fast shopping, banking, navigation
Communication Costs
• Video calls and file sharing are much cheaper than travelling
Efficiency
• Computers store and process data quickly
1
,Saving Labour
• Automation and robots complete tasks quicker
Accuracy and Reliability
• Computers perform tasks consistently with fewer errors
Effects on Time and Distance
• Instant communication across the world
Saving Paper
• Digital documents and online communication reduce paper use
Global Communication
• Networks and the internet enable social media
1.2 Data, Information, Knowledge, and Wisdom
Term Definition
Data Raw, unorganised facts that lack meaning on their own
Information Data that has been processed and organised to give it meaning
Knowledge Understanding gained from information; applying information to make
decisions
Wisdom Using knowledge and experience to make sound judgements and
decisions
1.3 Convergence
• It combines multiple technologies in one device
• Example: Smartphone
1.4 Social Implication and Environmental Impact
• Social connection is enhanced by computers
• Computers contribute to environmental issues such as high electricity use
Green Computing:
Reducing environmental impact through energy-efficient designs and biodegradable materials.
2
, Chapter 2: Hardware
Summary of Hardware
Component Type Purpose
INPUT DEVICES
Keyboard Standard / Laptop / Gaming / Enters information (letters) into
Virtual the computer
Pointing Device Mouse / Touchscreen / Controls movement of cursor on
Touchpad / Trackball screen
Scanning and Scanners / RFID / OCR Scans documents and converts
Reading Devices them to digital format
Video Devices Video Camera / Webcam Captures media and videos
Audio Devices Microphone / Voice Logger Communicates with computer
using a voice
Biometric Devices Fingerprint Scanner / Facial Measures a person's unique
Recognition characteristics
Point of Sale - Keeps track of retail stock and
prices
PROCESSING DEVICES
Motherboard - Connects all components
CPU - General processing of computer
GPU - Graphic processing
RAM - High speed, temporary storage
ROM - Information stored to turn
computer on
STORAGE DEVICES
Hard Disk Drive HDD (Internal / External) Slow, long-term storage
Solid State Drive SSD Fast, long-term storage
Flash Disk - Small, permanent storage device
(plug in)
Memory Cards - Permanent storage device for
digital information
CD / DVD / Blu-ray - Portable storage devices: data
can be copied
OUTPUT DEVICES
Display Devices LCD Monitor / TV Monitor / Displays images generated by
Projector computer
Printers Inkjet / Laser Converting soft copy to hard copy
3
