Understanding Computer Fundamentals: Data, Devices, and Memory
Why People Prefer Computers
Computers work faster than humans, find information quickly, store data efficiently, and operate tirelessly.
Data Types
Numeric: Integer and real.
Text: String.
Graphics: Pictures.
Date
Sound
Input Devices
Concept Keyboards
A flat board with programmable keys, used in primary education.
Light Pen
A pen-shaped wand with light sensors to select objects on screen.
Touch Screen
A flat screen that detects touch using infrared lasers, commonly found in restaurants.
OMR (Optical Mark Recognition)
Uses an optical mark reader to detect marks on forms, like lottery tickets.
OCR (Optical Character Recognition)
Uses a scanner and software to convert scanned text into editable format, used for sorting mail.
Binary Numbers
Computers use binary numbers (bits) for data storage and processing due to their simplicity in electronic circuits.
Memory
ROM (Read-Only Memory)
Permanent storage, non-volatile.
RAM (Random Access Memory)
Temporary working memory, volatile.
PROM (Programmable Read-Only Memory)
Programmable once, cannot be changed.
EPROM (Erasable Programmable Read-Only Memory)
Programmable and erasable, used in devices like washing machines.
EPOS and EFTPOS
EPOS (Electronic Point of Sale): Supermarket checkout terminals.
EFTPOS (Electronic Funds Transfer Point of Sale): Terminals for credit/debit card transactions.
Data Access
Direct Access: Data can be accessed immediately (random access).
Serial Access: Data is searched sequentially (magnetic tape).
File Compression
Reduces file size for storage and faster internet transfer. Requires decompression software like WinZip.
CAD (Computer-Aided Design)
Used for designing cars, buildings, circuit boards, aircraft, and kitchens.
Sensors
Monitor external conditions (temperature, pressure, light) and send data to computers. PIR sensors detect movement.
Formulae
Used in spreadsheets for calculations using symbols like +, -, *, /.