Basic Terminolgies
Computer – An electronic device that accepts data, processes it, and gives output.
Data – Raw facts and figures without meaning.
Information – Processed and meaningful data.
Processing – The act of converting data into information.
Instruction – A command given to a computer.
Program – A set of instructions to perform a task.
Hardware – Physical parts of a computer that can be touched.
Software – A collection of programs and instructions.
Firmware – Permanent software stored in ROM.
Liveware / Peopleware – The human users who operate the computer.
User – A person who uses the computer.
Input – Data entered into a computer.
Output – Result produced by the computer.
Storage – Place where data/information is kept.
Device – Any hardware component attached to a computer.
System – A combination of related parts working together.
Application – Software designed for specific tasks.
Utility – Software used for maintenance and protection.
File – A collection of related data stored together.
Folder / Directory – A place to store files.
Icon – A small graphical symbol representing a file/program.
Desktop – The main screen of an operating system.
Window – A rectangular area showing a program or file.
Taskbar – Bar showing running programs, usually at the bottom.
Booting – The process of starting a computer.
Rebooting – Restarting the computer.
Login / Logon – Entering credentials to access a system.
Logout / Logoff – Exiting from a system account.
Password – Secret code used for security.
Username – Name used to identify a user. Functional Unit Terminolgies
Input Unit – Accepts data and instructions from the user.
Output Unit – Displays or prints the processed result.
Memory Unit – Stores data, instructions, and results.
Control Unit (CU) – Controls and coordinates all operations of the computer.
Arithmetic Logic Unit (ALU) – Performs arithmetic and logical operations.
Central Processing Unit (CPU) – The brain of the computer; consists of CU and ALU.
Register – Small and fastest memory inside CPU.
Accumulator (AC) – Register used to store intermediate arithmetic results.
Program Counter (PC) – Holds the address of the next instruction.
Instruction Register (IR) – Stores the current instruction being executed.
Memory Address Register (MAR) – Stores the address of memory location to access.
Memory Data Register (MDR) / MBR – Stores data being transferred to/from memory.
Cache Memory – Very fast memory between CPU and RAM.
Bus – Pathway for data transfer inside the computer.
Data Bus – Carries data between components.
Address Bus – Carries memory addresses.
Control Bus – Carries control signals.
Clock – Generates timing signals for operations.
Clock Speed – Number of cycles per second, measured in Hertz.
Machine Cycle – Complete process of instruction execution.
Fetch Cycle – Fetching instruction from memory.
Decode Cycle – Interpreting the instruction.
Execute Cycle – Performing the instruction.
Store Cycle – Storing the result back in memory. Basic TerminolgiesCPU – The brain of the computer that processes instructions.
Microprocessor – A CPU on a single integrated chip.
Processor – Another name for CPU.
Core – An individual processing unit inside a CPU.
Single-Core Processor – CPU with one core.
Dual-Core Processor – CPU with two cores.
Quad-Core Processor – CPU with four cores.
Octa-Core Processor – CPU with eight cores.
Thread – A sequence of instructions handled by a CPU.
Multithreading – Running multiple threads simultaneously.
Clock – Produces pulses to synchronize operations.
Clock Speed – Number of cycles per second (Hz, GHz).
Cycle – One complete pulse of the clock.
Instruction Cycle – Time to complete one instruction.
Machine Cycle – Basic operation cycle of CPU.
Fetch – Getting instruction from memory.
Decode – Understanding the instruction.
Execute – Performing the instruction.
Store – Saving the result.
Register – Small, high-speed storage inside CPU.
Accumulator – Stores arithmetic results temporarily.
Program Counter (PC) – Holds address of next instruction.
Instruction Register (IR) – Holds current instruction.
MAR – Holds memory address.
MDR / MBR – Holds data being transferred.
Cache Memory – Fast memory to speed up CPU access.
L1 Cache – Smallest and fastest cache.
L2 Cache – Larger but slower than L1.
L3 Cache – Shared cache among cores.
Heat Sink – Removes heat from CPU.
Fan / Cooler – Cools the processor.
GPU – Specialized processor for graphics.
Coprocessor – Assists CPU in special tasks.
Overclocking – Running CPU faster than standard speed.
Underclocking – Running CPU slower to save power.
Instruction Set – Collection of commands CPU understands.
x86 – Common CPU architecture by Intel / AMD.
ARM – Power-efficient CPU architecture used in phones.
64-bit Processor – Can process 64 bits at once.
32-bit Processor – Can process 32 bits at once.Memory Storage
- Memory – Place where data and instructions are stored in a computer.
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Storage – Long-term saving of data for future use.
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Primary Memory – Main memory directly accessed by CPU.
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Secondary Memory – Permanent storage used for saving data long-term.
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RAM (Random Access Memory) – Temporary memory that stores data while computer is running.
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ROM (Read Only Memory) – Permanent memory that stores essential startup instructions.
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Cache Memory – Very fast memory between CPU and RAM to speed up processing.
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Register – Smallest and fastest memory inside CPU.
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Virtual Memory – Memory technique using hard disk as extra RAM.
Types of RAM
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DRAM (Dynamic RAM) – Needs constant refreshing; used in main memory.
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SRAM (Static RAM) – Faster and does not need refreshing; used in cache.
Types of ROM
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PROM – Programmable once; cannot be erased.
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EPROM – Can be erased using UV light and reprogrammed.
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EEPROM – Can be electrically erased and rewritten.
Secondary Storage Devices
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Hard Disk (HDD) – Magnetic storage device with large capacity.
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SSD (Solid State Drive) – Faster storage using flash memory.
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USB Flash Drive – Portable storage device.
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Memory Card – Small storage used in phones/cameras.
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Optical Disk – CD, DVD, Blu-ray storage using laser.
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Magnetic Tape – Tape-based storage used for backup.
Memory Units
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Bit – Smallest unit of data (0 or 1).
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Nibble – 4 bits.
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Byte – 8 bits.
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Kilobyte (KB) – 1024 bytes.
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Megabyte (MB) – 1024 KB.
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Gigabyte (GB) – 1024 MB.
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Terabyte (TB) – 1024 GB.
Access Types
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Random Access – Data accessed in any order (RAM).
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Sequential Access – Data accessed in order (Magnetic tape).
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Direct Access – Data accessed directly by location (HDD).
Other Important Terms
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Volatile Memory – Loses data when power is off (RAM).
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Non-Volatile Memory – Keeps data even when power is off (ROM, HDD).
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Buffer Memory – Temporary storage during data transfer.
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Flash Memory – Fast, rewritable non-volatile memory.
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Swap Space – Part of disk used as virtual RAM.
- Formatting – Setting up a disk so it can store files and folders.
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File System – Method used to organize and manage files (e.g., FAT32, NTFS).
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Low-Level Formatting – Creates physical tracks and sectors on the disk (done by manufacturer).
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High-Level Formatting – Creates file system and directory structure (done by user/OS).
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Partitioning – Dividing a disk into separate logical sections.
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Partition – A divided section of a hard disk.
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Boot Sector – First sector of a disk that contains boot information.
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Sector – Smallest storage unit on a disk.
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Track – Circular path on a disk where data is stored.
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Cluster – Group of sectors treated as one unit for storage.
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Quick Format – Removes file system structure quickly without deep checking.
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Full Format – Deletes data and checks disk for errors.
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Erase – Removing all data from storage.
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Volume – Formatted storage area with a file system.
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Allocation Table (FAT) – Table that keeps track of file locations.
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NTFS – Advanced file system used in modern Windows systems.
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Bad Sector – Damaged part of disk that cannot store data.
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Disk Cleanup – Removing unnecessary files to free space.
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Disk Defragmentation – Rearranging fragmented data for faster access.
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Mounting – Making a storage device accessible to the system.
Input Device
- Input Device – Hardware used to enter data and instructions into a computer.
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Keyboard – Used to type text, numbers, and commands.
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Mouse – Pointing device used to move cursor and select items.
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Scanner – Converts printed documents into digital form.
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OCR (Optical Character Recognition) – Converts scanned text into editable text.
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OMR (Optical Mark Recognition) – Reads shaded marks in forms or answer sheets.
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MICR (Magnetic Ink Character Recognition) – Reads special ink used in bank cheques.
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Barcode Reader – Reads product information using barcode lines.
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QR Code Reader – Reads two-dimensional QR codes.
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Joystick – Used mainly for gaming and controlling movement.
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Light Pen – Pen-like device used to draw or select on screen.
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Touch Screen – Screen that works by touching directly.
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Microphone – Converts sound into digital input.
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Webcam – Captures video and images as input.
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Trackball – Stationary pointing device controlled by rolling a ball.
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Graphics Tablet – Used for drawing digitally with a pen.
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Touchpad – Small touch-sensitive surface used in laptops.
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Biometric Devices – Input using human features (fingerprint, face, iris).
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Fingerprint Scanner – Reads fingerprint patterns for security.
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Voice Input System – Converts spoken words into computer commands.
Output Device
- Output Device – Hardware that shows or produces results from a computer.
- Monitor / VDU – Displays text, images, and video on screen.
- Printer – Produces hard copy (paper output) of data.
Key related terms:
- Printer – Device that converts soft copy into hard copy.
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Hard Copy – Printed output on paper.
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Soft Copy – Digital output on screen.
Types of Printers:
- Impact Printer – Prints by striking an ink ribbon (noisy).
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Non-Impact Printer – Prints without striking (quiet).
Impact Printers:
- Dot Matrix Printer – Prints using pins forming dots on paper.
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Daisy Wheel Printer – Uses wheel with characters for printing (old type).
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Line Printer – Prints a full line at once (used in big systems).
Non-Impact Printers:
- Inkjet Printer – Sprays tiny ink droplets to print.
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Laser Printer – Uses laser and toner for fast, high-quality printing.
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Thermal Printer – Uses heat to print (used in receipts).
Printer Concepts:
- Resolution – Quality of print measured in DPI (dots per inch).
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DPI (Dots Per Inch) – Number of dots printed per inch.
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Cartridge – Ink container in printer.
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Toner – Powder used in laser printers.
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Spooler – Software that manages print jobs.
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Print Queue – List of documents waiting to print.
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Duplex Printing – Printing on both sides of paper.
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Printing Speed – Measured in PPM (pages per minute).
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Printer Driver – Software that controls printer operation.
- Speaker – Outputs sound from the computer.
- Headphones – Personal audio output device.
- Plotter – Prints large-scale drawings like maps and designs.
Plotter (Computer Fundamentals) – An output device used to print large and high-precision graphics like maps, engineering drawings, and architectural designs.
Key related terms:
- Plotter – A device that draws images on paper using pens or ink.
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Hard Copy Output – Physical print produced on paper.
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Vector Graphics – Graphics made of lines and shapes used by plotters.
Types of Plotters:
- Drum Plotter – Paper moves on a rotating drum while pen draws.
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Flatbed Plotter – Paper remains fixed; pen moves over it.
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Inkjet Plotter – Uses inkjet technology for large prints.
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Cutting Plotter – Cuts materials instead of printing (used in stickers, designs).
Plotter Components:
- Pen/Marker – Drawing tool used in plotter.
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Paper – Medium where output is drawn.
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Carriage – Moves the pen across paper.
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Motor System – Controls movement of pen and paper.
Important Concepts:
- Resolution – Quality/detail of output drawing.
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Precision – Accuracy in drawing fine lines.
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CAD (Computer Aided Design) – Software used with plotters.
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Large Format Printing – Printing on big sheets (A1, A0).
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Graphic Plotting – Process of drawing technical diagrams.
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Vector Output – Output based on mathematical lines instead of pixels.
- Projector – Displays computer output on a large screen or wall.
- Monitors
- LCD Monitor – Thin flat-screen display using liquid crystal technology.
- LED Monitor – Improved LCD using LED backlighting.
- CRT Monitor – Old bulky monitor using cathode ray tube.
- Inkjet Printer – Prints by spraying ink on paper.
- Laser Printer – Uses laser technology for fast and high-quality printing.
- Dot Matrix Printer – Prints using pins and ink ribbon (impact printer).
- 3D Printer – Creates physical 3D objects from digital design.
- Braille Printer (Embosser) – Prints tactile output for visually impaired users.
- Sound Card Output – Converts digital sound into audible audio.
- Video Card Output – Sends graphics/video to monitor.
- Haptic Device – Gives vibration/force feedback as output.
- Smart Display Devices – Output through smart TVs or smart panels.
- Soft Copy Output – Output shown on screen (digital form).
Types of Computer
Types of Computer (Computer Fundamentals) – Computers are classified based on size, working principle, and purpose.
1. Based on Working Principle
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Analog Computer – Works with continuous signals (used in speed, temperature measurement).
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Digital Computer – Works with binary data (0 and 1), most common type.
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Hybrid Computer – Combination of analog and digital computer.
2. Based on Size and Capacity
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Microcomputer – Small personal computer (PC, laptop).
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Minicomputer – Medium-sized computer used by organizations.
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Mainframe Computer – Large computer used by big companies for bulk data processing.
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Supercomputer – Fastest and most powerful computer used in scientific research.
3. Based on Purpose
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General Purpose Computer – Used for multiple tasks (word, internet, games).
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Special Purpose Computer – Designed for a specific task (ATM, traffic control).
4. Modern/Advanced Types
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Workstation – High-performance single-user computer for design and engineering.
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Server Computer – Provides services to other computers in a network.
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Embedded Computer – Built inside devices like washing machines, cars, etc.
Number System
Number System – A method of representing numbers using symbols and a base.
Base (Radix) – Total number of digits used in a number system.
Digit – A single symbol used to form numbers.
Decimal System – Number system with base 10 (0–9).
Binary System – Number system with base 2 (0 and 1).
Octal System – Number system with base 8 (0–7).
Hexadecimal System – Number system with base 16 (0–9, A–F).
Binary Digit (Bit) – Smallest unit of data (0 or 1).
Nibble – A group of 4 bits.
Byte – A group of 8 bits.
Word – A group of bits processed as a unit by CPU.
Positional Value – Value of a digit based on its position.
Place Value – Weight of a digit in a number system.
MSB (Most Significant Bit) – Leftmost bit with highest value.
LSB (Least Significant Bit) – Rightmost bit with lowest value.
Binary Number – A number written in base 2.
Octal Number – A number written in base 8.
Hex Number – A number written in base 16.
Conversion – Changing number from one system to another.
Binary to Decimal – Converting base 2 number into base 10.
Decimal to Binary – Converting base 10 number into base 2.
Binary Addition – Adding binary numbers using rules of 0 and 1.
Binary Subtraction – Subtracting binary numbers using borrow method.
Weighted Number System – Each digit has a positional weight.
Non-weighted System – Digits have no positional weight (rare).
Overflow – When result exceeds storage capacity.
Underflow – When value is too small to represent.
Base Conversion – Process of changing number base.
Complement – Method used in subtraction (1’s and 2’s complement).
1’s Complement – Inverting all bits (0 ↔ 1).
2’s Complement – 1’s complement + 1, used for subtraction.
Operating System
Operating System (OS) – System software that acts as an interface between user and computer hardware.
Kernel – Core part of OS that controls CPU, memory, and devices.
Shell – Interface between user and OS (CLI or GUI).
Booting – Process of starting or loading the operating system.
Cold Booting – Starting computer from completely off state.
Warm Booting – Restarting the computer while it is already ON.
Multitasking – Running multiple programs at the same time.
Multiprogramming – Multiple programs kept in memory and executed one by one.
Multiprocessing – Using more than one CPU to execute tasks.
Time Sharing – Multiple users share CPU time simultaneously.
Real-Time OS – OS that gives instant response to inputs.
Single User OS – Supports only one user at a time.
Multi User OS – Supports multiple users at the same time.
GUI (Graphical User Interface) – OS interface with icons and graphics.
CLI (Command Line Interface) – Text-based command interface.
File Management – Organizing, storing, and retrieving files.
Process Management – Handling execution of programs.
Memory Management – Managing primary memory (RAM).
Device Management – Controlling input/output devices.
Security Management – Protecting system from unauthorized access.
System Call – Request from program to OS for services.
Driver – Software that controls hardware devices.
Utility Program – Helps in maintenance (antivirus, disk cleanup).
Deadlock – Situation where processes block each other.
Spooling – Storing data temporarily for devices like printer.
Buffering – Temporary storage during data transfer.
Paging – Memory management technique dividing memory into pages.
Segmentation – Dividing memory into logical sections.
Virtual Memory – Using disk space as extended RAM.
Scheduler – OS component that decides process execution order.File Database
File Related Terms
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File – A collection of related data stored under a name.
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Filename – Name given to a file for identification.
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File Extension – Indicates file type (e.g., .txt, .jpg).
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Folder / Directory – A container used to store files.
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Subdirectory – Folder inside another folder.
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Path – Location of a file in storage.
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File System – Method used by OS to manage files.
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File Management – Organizing, storing, and retrieving files.
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Sequential File – Data stored and accessed in order.
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Direct File – Data accessed directly using address.
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Indexed File – File accessed using an index table.
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Read Operation – Opening and viewing a file.
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Write Operation – Saving data into a file.
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Append – Adding data at the end of a file.
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Delete File – Removing a file from storage.
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Rename File – Changing file name.
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File Permission – Rights like read, write, execute.
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Backup – Copy of file for safety.
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Restore – Recovering backed-up file.
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File Compression – Reducing file size.
Database Related Terms
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Database – Organized collection of related data.
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DBMS (Database Management System) – Software to manage databases.
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Table – Data arranged in rows and columns.
- Table – Collection of related data organized in rows and columns.
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Row (Record) – A single entry in a table containing full data of one item.
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Column (Field) – A category of data in a table (attribute).
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Field – Smallest unit of data in a table (one column value).
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Record – Complete set of fields in one row.
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Cell – Intersection of a row and column (single value).
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Attribute – Another name for column/field.
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Tuple – Another name for row/record (database term).
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Primary Key – Unique field that identifies each record.
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Foreign Key – Field that connects one table to another.
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Schema – Structure/design of a table.
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Data Type – Type of data stored in a column (text, number, date).
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Heading – Name of each column.
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Entity – Object or thing about which data is stored.
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Relation – Another name for table in DBMS.
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Degree – Number of columns in a table.
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Cardinality – Number of rows in a table.
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Null Value – Empty or unknown data in a cell.
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Index – Structure used to speed up data search.
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Query Result Table – Output table generated after a database query.
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Query – Request to retrieve or manipulate data.
- Query – A command used to interact with a database to get or modify data.
- SQL (Structured Query Language) – Language used to write database queries.
- SELECT Query – Used to retrieve data from a table.
- INSERT Query – Used to add new data into a table.
- UPDATE Query – Used to modify existing data.
- DELETE Query – Used to remove data from a table.
- WHERE Clause – Condition used to filter data in a query.
- ORDER BY – Sorts query result in ascending or descending order.
- GROUP BY – Groups similar data together in query results.
- JOIN Query – Combines data from two or more tables.
- INNER JOIN – Returns matching records from both tables.
- LEFT JOIN – Returns all records from left table and matching from right.
- RIGHT JOIN – Returns all records from right table and matching from left.
- FULL JOIN – Returns all records from both tables.
- Condition – Rule used to filter data in query.
- Expression – Combination of fields and operators in query.
- Result Set – Output generated after executing a query.
- Subquery – Query inside another query.
- Command – Instruction written in SQL.
- Transaction Query – Query that ensures complete execution of operations.
- Data Redundancy – Repetition of same data.
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Data Integrity – Accuracy and consistency of data.
- Data Integrity – Accuracy and consistency of data in a database.
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Accuracy – Data is correct and error-free.
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Consistency – Same data remains uniform in all places.
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Validity – Data follows defined rules and format.
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Reliability – Data can be trusted for use.
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Entity Integrity – Each table must have a unique primary key.
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Referential Integrity – Relationship between tables remains valid using foreign keys.
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Domain Integrity – Data must be within allowed range/type.
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Primary Key – Ensures uniqueness of each record.
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Foreign Key – Maintains relationship between tables.
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Constraints – Rules applied to data (NOT NULL, UNIQUE, etc.).
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Data Validation – Checking data before storing it.
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Error Checking – Detecting mistakes in data.
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Duplicate Data – Repeated data that reduces integrity.
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Data Redundancy – Unnecessary repetition of data.
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Normalization – Process of reducing redundancy and improving integrity.
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Consistency Check – Ensuring data is same across system.
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Transaction Integrity – Ensuring complete and correct execution of database operations.
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Backup Integrity – Ensuring backup data is correct and usable.
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Security Control – Protecting data from unauthorized changes.
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Data Security – Protection of data from unauthorized access.
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Normalization – Process of organizing data efficiently.
- Normalization – Process of dividing large tables into smaller related tables to avoid duplication.
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Redundancy – Repetition of the same data in multiple places.
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Anomaly – Problem caused by poor database design (insert, update, delete errors).
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Insertion Anomaly – Problem when adding data due to missing fields.
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Update Anomaly – Problem when updating data causes inconsistency.
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Deletion Anomaly – Loss of important data when deleting a record.
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Functional Dependency – Relationship where one attribute depends on another.
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Primary Key – Unique identifier used to maintain table structure.
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Foreign Key – Connects two related tables.
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Candidate Key – Possible attributes that can become primary key.
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Composite Key – Primary key made using more than one field.
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1NF (First Normal Form) – No repeating groups; atomic values only.
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2NF (Second Normal Form) – Removes partial dependency.
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3NF (Third Normal Form) – Removes transitive dependency.
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BCNF (Boyce-Codd Normal Form) – Stronger version of 3NF.
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Table Decomposition – Splitting large tables into smaller ones.
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Dependency – One field depends on another field.
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Attribute – Column in a table.
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Tuple – Row in a table.
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Schema – Structure/design of database tables.
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Relationship – Connection between tables.
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ER Diagram – Visual representation of database structure.
- ER Diagram – Graphical representation of database structure.
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Entity – Real-world object or thing (e.g., Student, Teacher).
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Attribute – Property or characteristic of an entity (e.g., Name, Age).
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Relationship – Connection between entities (e.g., Student studies Course).
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Entity Set – Collection of similar entities.
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Attribute Set – Collection of attributes of an entity.
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Primary Key – Unique identifier of an entity.
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Composite Attribute – Attribute that can be divided (e.g., Full Name → First + Last).
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Simple Attribute – Cannot be divided further (e.g., Age).
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Derived Attribute – Calculated from other attributes (e.g., Age from DOB).
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Multi-valued Attribute – Can have multiple values (e.g., Phone Numbers).
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Weak Entity – Entity that depends on another entity for identification.
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Strong Entity – Entity that can exist independently.
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Cardinality – Relationship type between entities (1:1, 1:M, M:M).
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One-to-One (1:1) – One entity relates to one other entity.
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One-to-Many (1:M) – One entity relates to many entities.
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Many-to-Many (M:M) – Many entities relate to many entities.
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Participation Constraint – Whether entity must participate in relationship.
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Total Participation – All entities must participate in relationship.
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Partial Participation – Some entities participate in relationship.
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ER Model – Conceptual model used before database creation.
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Rectangles – Represent entities in diagram.
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Ovals – Represent attributes.
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Diamonds – Represent relationships.
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DBA (Database Administrator) – Person who manages database.
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Transaction – A complete unit of database operation.
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Backup (Database) – Copy of database for safety.
- Transaction – A group of operations treated as one unit (all succeed or all fail).
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Atomicity – Either all operations happen or none happen.
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Consistency – Database remains in a valid state after transaction.
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Isolation – One transaction does not affect another running transaction.
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Durability – Once completed, changes are permanent.
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ACID Properties – Four rules that ensure safe transactions (Atomicity, Consistency, Isolation, Durability).
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Commit – Saves all changes made by a transaction permanently.
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Rollback – Cancels a transaction and restores previous state.
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Savepoint – Temporary checkpoint within a transaction.
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Transaction Log – Record of all database changes.
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Concurrent Transaction – Multiple transactions running at the same time.
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Deadlock – Situation where two transactions wait for each other forever.
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Commit Point – Stage where transaction is successfully completed.
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Failure – Error that causes transaction to stop or rollback.
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Read Operation – Retrieving data in transaction.
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Write Operation – Modifying data in transaction.
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Undo – Reversing changes of a transaction.
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Redo – Reapplying changes after failure.
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Consistency Check – Ensures rules are not violated after transaction.
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Transaction Manager – System component that controls transactions.
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Recovery – Restoring lost database data.
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Concurrency – Multiple users accessing database at same time.
Networking
Network – A group of interconnected computers.
Networking – Process of connecting computers to share resources.
Node – Any device connected in a network.
Host – A computer that provides or uses network services.
Client – A device that requests services from a server.
Server – A computer that provides services or data.
Peer – A computer that acts as both client and server.
LAN (Local Area Network) – Network within a small area like school or office.
- LAN – Local Area Network used for small-area communication.
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Local Area – Limited area such as home, school, or office.
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Network – Group of connected computers sharing resources.
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Node – Any device connected in a LAN (PC, printer, etc.).
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Server – Central computer that provides services in LAN.
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Client – Computer that uses services from server.
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Peer-to-Peer Network – LAN where all computers are equal.
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Client-Server Network – LAN with central server control.
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Topology – Layout of LAN (Star, Bus, Ring, etc.).
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Ethernet – Common technology used in LAN.
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Switch – Device that connects multiple computers in LAN.
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Hub – Simple device that broadcasts data to all devices.
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Router – Connects LAN to other networks or internet.
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Bandwidth – Data transfer capacity of LAN.
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Transmission Media – Cable or wireless used in LAN.
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UTP Cable – Common twisted pair cable used in LAN.
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Wi-Fi – Wireless LAN technology.
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MAC Address – Unique hardware address of LAN device.
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IP Address – Logical address of device in LAN.
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File Sharing – Sharing data between computers in LAN.
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Printer Sharing – Using one printer by multiple computers.
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Resource Sharing – Sharing hardware/software in LAN.
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Protocol – Rules for communication (TCP/IP).
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Latency – Delay in LAN communication.
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LAN Speed – Usually high compared to WAN.
MAN (Metropolitan Area Network) – Network covering a city area.
MAN – Network that covers a city or large town.
Metropolitan Area – Area larger than LAN but smaller than WAN.
LAN – Smaller network that connects to form MAN.
WAN – Larger network that connects multiple MANs.
Node – Any device connected in MAN.
Backbone Network – High-speed main network of MAN.
Fiber Optic Cable – Common high-speed medium used in MAN.
Wireless MAN (WiMAX) – Wireless technology used for MAN.
ISP (Internet Service Provider) – Provides MAN/WAN connectivity.
Router – Connects different LANs in MAN.
Switch – Connects devices within LANs in MAN.
Bridge – Connects two LANs inside MAN.
Bandwidth – Data transfer capacity of MAN.
Transmission Media – Cable or wireless used for communication.
Public Network – MAN often uses shared infrastructure.
Private MAN – MAN owned by an organization or government.
Cable TV Network – Example of MAN.
City Network – Government or city-wide communication system.
High Speed Connection – MAN is faster than WAN.
Coverage Area – Usually 5 km to 50 km range
WAN (Wide Area Network) – Network covering large areas like countries.
WAN – Wide Area Network covering large distances.
Wide Area – Large geographical region (country or world).
LAN – Small network that connects into WAN.
MAN – City-level network that connects to WAN.
Internet – The largest example of WAN.
Node – Any device connected in WAN.
Router – Device used to connect different networks in WAN.
Gateway – Connects different types of networks in WAN.
ISP (Internet Service Provider) – Provides WAN connectivity to users.
Leased Line – Dedicated connection used in WAN.
Satellite Communication – Wireless method used in WAN.
Fiber Optic Cable – High-speed medium used in WAN.
Microwave Transmission – Wireless communication used in WAN.
Packet Switching – Method of sending data in small packets.
IP Address – Unique address of devices in WAN.
DNS (Domain Name System) – Converts domain names to IP addresses.
Latency – Delay in data transmission over WAN.
Bandwidth – Amount of data transferred in WAN.
Protocol (TCP/IP) – Rules for communication in WAN.
Public Network – WAN is mostly public and global.
Global Connectivity – WAN connects the whole world.
Internet Backbone – Main high-speed network of WAN.
Cloud Network – Internet-based WAN services.
Security Firewall – Protects WAN from threats.
Data Transmission – Process of sending data across WAN.
PAN (Personal Area Network) – Very small network around a person.
Internet – Global network of interconnected computers.
Internet – Worldwide network of connected computers.
Network of Networks – Internet connects many LANs, MANs, and WANs.
WAN – Internet is the largest form of WAN.
TCP/IP – Main protocol used for internet communication.
IP Address – Unique address of each device on internet.
Domain Name – Human-readable name of website (e.g., google.com).
DNS (Domain Name System) – Converts domain names into IP addresses.
WWW (World Wide Web) – Collection of websites on the internet.
Web Browser – Software used to access internet (Chrome, Firefox).
Web Server – Stores and delivers web pages.
URL (Uniform Resource Locator) – Address of a web page.
HTTP/HTTPS – Protocols used to access websites.
Hyperlink – Clickable link to navigate between pages.
Search Engine – Tool to find information (Google, Bing).
ISP (Internet Service Provider) – Company that provides internet access.
Modem – Device that connects computer to internet.
Router – Distributes internet to multiple devices.
Bandwidth – Speed/amount of data transfer.
Upload – Sending data to internet.
Download – Receiving data from internet.
Cloud Computing – Storing and accessing data via internet.
Email – Electronic mail service over internet.
Social Media – Platforms like Facebook and X.
Cyber Security – Protection of internet systems and data.
Firewall – Security system that protects network.
Cookies – Small data stored by websites in browser.
Cache – Temporary storage for faster browsing.
Streaming – Watching/using media in real-time over internet.
FTP (File Transfer Protocol) – Used to transfer files online.
E-commerce – Buying and selling goods over internet.
Intranet – Private network within an organization.
Intranet – Private internal network of an organization.
Private Network – Access is restricted to employees or members only.
Organization Network – Used inside companies, schools, offices.
LAN-Based System – Usually built on Local Area Network.
TCP/IP – Protocol used for communication inside intranet.
Web Browser – Used to access intranet websites.
Intranet Server – Stores internal data and applications.
Firewall – Protects intranet from external access.
User Authentication – Login system for authorized access.
Internal Communication – Used for messaging within organization.
File Sharing – Sharing documents inside organization.
Database Access – Internal data storage and retrieval.
Employee Portal – Website inside intranet for staff use.
Email System – Internal email service.
Restricted Access – Only authorized users can enter.
Security Policy – Rules to protect internal data.
Intranet Website – Internal web pages of organization.
Local Hosting – Data stored on local servers.
Intranet vs Internet – Intranet is private, Internet is public.
Extranet Connection – Controlled access extension of intranet.
Extranet – Controlled access network for outsiders and organization.
Topology – Arrangement of computers in a network.
Bus Topology – All devices connected in a single line.
Star Topology – Devices connected through a central hub/switch.
Ring Topology – Devices connected in a circular path.
Mesh Topology – Every device connected to every other device.
Hybrid Topology – Combination of different topologies.
Protocol – Rules for communication between devices.
TCP/IP – Main protocol used in internet communication.
IP Address – Unique address of a device in network.
MAC Address – Hardware address of a network device.
DNS (Domain Name System) – Converts domain names into IP addresses.
URL (Uniform Resource Locator) – Address of a web page.
HTTP/HTTPS – Protocol used for web communication.
FTP (File Transfer Protocol) – Used to transfer files.
Bandwidth – Amount of data transfer capacity.
Router – Device that connects different networks.
Switch – Device that connects computers within a network.
Hub – Simple device that broadcasts data to all devices.
Modem – Converts digital signals to analog and vice versa.
Gateway – Connects different types of networks.
Firewall – Security system that protects network.
Bandwidth – Speed of data transfer.
Latency – Delay in data transmission.
Packet – Small unit of data sent over network.
Packet Switching – Method of sending data in packets.
Transmission Media – Medium used to send data (cable/wireless).Security
Security – Protection of computer resources and information.
Cyber Security – Protection of systems from digital attacks.
Information Security – Safeguarding data from unauthorized access.
Authentication – Verifying identity of a user (login/password).
Authorization – Giving permission to access resources.
Username – Identity name used to access system.
Password – Secret code used for security.
Biometric Security – Security using fingerprints, face, iris, etc.
Encryption – Converting data into unreadable form for safety.
Decryption – Converting encrypted data back to original form.
Firewall – System that blocks unauthorized network access.
Antivirus – Software that detects and removes viruses.
Malware – Harmful software that damages systems.
Virus – Malicious program that spreads and harms files.
Worm – Self-replicating malware that spreads automatically.
Trojan Horse – Harmful program disguised as useful software.
Spyware – Software that secretly collects user data.
Adware – Software that shows unwanted advertisements.
Ransomware – Malware that locks data and demands money to unlock it.
Rootkit – Malware that hides itself and gives hacker control of system.
Keylogger – Records keystrokes to steal passwords and data.
Botnet – Network of infected computers controlled by attacker.
Backdoor – Secret entry point into a system bypassing security.
Logic Bomb – Malware activated by a specific condition or time.
Payload – Part of malware that performs harmful action.
Infection – Process of malware entering a system.
Propagation – Spreading of malware to other systems.
Antivirus – Software used to detect and remove malware.
Firewall – Blocks unauthorized access to prevent malware attack.
Quarantine – Isolating infected files from system.
Scan – Checking system for malware.
Threat – Any potential danger to computer system.
Phishing – Fake attempts to steal personal information.
Hacking – Unauthorized access to a system.
Ethical Hacking – Legal testing of system security.
Backup – Copy of data for recovery in case of loss.
Recovery – Restoring lost or damaged data.
Access Control – Restricting who can use system resources.
Security Policy – Rules for protecting systems and data.
Digital Signature – Electronic verification of identity.
SSL/TLS – Secure protocols for safe internet communication.
Two-Factor Authentication (2FA) – Extra security step using OTP or device.
Firewall Rules – Conditions used to allow/block network traffic.
Data Breach – Unauthorized access to sensitive data.Programming
Programming – Writing a set of instructions for a computer.
Program – A collection of instructions that performs a task.
Programming Language – Language used to write programs (C, Java, Python).
Source Code – Human-readable instructions written by programmer.
Machine Code – Binary code (0s and 1s) understood by computer.
High-Level Language – Easy-to-understand language (C, Java, Python).
Low-Level Language – Close to machine language (Assembly).
Algorithm – Step-by-step solution to a problem.
Flowchart – Diagram that represents algorithm visually.
Pseudo Code – Simple English-like representation of program logic.
Compiler – Converts entire program into machine code at once.
Interpreter – Converts and executes code line by line.
Assembler – Converts assembly language into machine code.
Syntax – Rules of writing a programming language.
Variable – Named storage location for data.
Constant – Value that does not change during program execution.
Data Type – Type of data (int, float, char, etc.).
Operator – Symbol used for operations (+, -, *, /).
Loop – Repeating a set of instructions.
Conditional Statement – Decision-making statement (if, else).
Function – Block of code that performs a specific task.
Array – Collection of similar data items.
Debugging – Finding and fixing errors in program.
Bug – Error in a program.
Execution – Running a program.
IDE (Integrated Development Environment) – Software for writing programs.
Runtime Error – Error during program execution.
Compile Time Error – Error detected during compilation.
Logic Error – Wrong output due to incorrect logic.
Algorithm Efficiency – Measure of program performance.Internet
- Internet – Global network of interconnected computers used for communication and information sharing.
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WWW (World Wide Web) – Collection of websites accessed through internet.
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Web Browser – Software used to access internet (Chrome, Firefox).
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URL – Address of a web page.
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ISP (Internet Service Provider) – Company that provides internet access.
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IP Address – Unique address of a device on internet.
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DNS – Converts domain names into IP addresses.
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HTTP/HTTPS – Protocol used for web communication.
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Download – Receiving data from internet.
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Upload – Sending data to internet.
2. Cloud Computing
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Cloud Computing – Using internet to store, manage, and process data instead of local computer.
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Cloud – Remote servers used for data storage and services.
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SaaS (Software as a Service) – Software provided over internet (e.g., Gmail).
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PaaS (Platform as a Service) – Platform for developing applications online.
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IaaS (Infrastructure as a Service) – Virtual hardware resources over internet.
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Cloud Storage – Online storage of files (Google Drive).
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Virtualization – Creating virtual resources using cloud.
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Scalability – Ability to increase/decrease resources easily.
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Pay-as-you-go – Payment based on usage.
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Backup – Storing data safely in cloud.
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Data Center – Large facility that stores cloud servers.
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Public Cloud – Cloud services available to everyone.
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Private Cloud – Cloud used by a single organization.
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Hybrid Cloud – Combination of public and private cloud.
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Cloud Security – Protection of data stored in cloud.
3. IoT (Internet of Things)
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IoT (Internet of Things) – Network of physical devices connected to internet that can collect and exchange data.
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Smart Device – Device that can connect and communicate via internet.
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Sensor – Device that collects data from environment.
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Actuator – Device that performs action based on data.
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Smart Home – Home devices controlled through internet.
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Wearable Devices – Smart devices worn on body (smartwatch).
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Automation – Automatic control of devices without human input.
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Machine-to-Machine (M2M) – Devices communicating with each other.
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Smart City – City using IoT for traffic, lighting, and services.
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Embedded System – Computer system built inside devices.
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Data Collection – Gathering information from sensors.
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Remote Monitoring – Controlling devices from anywhere.
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Connectivity – Devices connected via Wi-Fi, Bluetooth, etc.
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Cloud Integration – IoT devices storing data in cloud.
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Smart Agriculture – Using IoT in farming systems.