Computer Science Basics Quiz

Computer Generations

• Fourth Generation (1971-1980)
  • Very Large Scale Integration (VLSI) circuits were introduced, making computers more compact and affordable.
  • Real-time, time-sharing, and distributed operating systems were commonly used.
  • Popular programming languages included C and C++.
• Fifth Generation (1980–Present)
  • Ultra Large Scale Integration (ULSI) technology was introduced.
  • Microprocessors contained millions of components.
  • Parallel processing and AI software became prominent.
  • Programming languages: C, C++, Java, and .Net.
  • Devices: Desktop, Laptop, Notebook, and Ultrabook.

Computer Basics

• A computer is an electronic device that processes raw data into meaningful information.
• It executes instructions (programs) to perform tasks.
• The full form of "computer" is "Commonly Operated Machine Particularly Used for Training, Education, and Research."

Computer Components

• Hardware:
  • Central Processing Unit (CPU)
  • Memory (RAM/Storage devices)
  • Input/Output devices (keyboard, mouse, etc.)
  • Peripherals (printers, scanners)
• Software:
  • Operating system (OS)
  • Applications (software programs)

History of Computers

• Early developments: Analytical Engine and tabulating machines in the 19th century.
• Modern computers emerged in the mid-20th century with transistors and integrated circuits.

Importance and Uses of Computers

• Widely used in industries like education, finance, healthcare, and entertainment.
• Enabled advancements such as the internet, cloud computing, and mobile devices.

Computer Functions

• Accepts data
• Stores data
• Processes data based on instructions
• Retrieves stored data
• Outputs results in a desired format

Data and Information

• Data: Raw facts and figures entered into a computer, unorganized and without inherent meaning. Examples: numbers, words, images, sounds.
• Information: Data that has been processed, organized, and given context to become meaningful and useful. Example: Sales figures processed into a graph showing trends over time, which can aid in decision-making.

Classification of Computers

Based on Design and Technology

• Digital Computers: Process information in discrete (binary) form (0s and 1s). Common in industrial, business, and scientific applications. Suitable for large-volume data processing.
• Analog Computers: Process continuous data, often from physical processes. Example: Thermometers, simulations in aircrafts and nuclear power plants. Suitable for real-time simulation tasks.
• Hybrid Computers: Combine analog and digital technology. Provide the speed of analog and accuracy of digital. Common in complex simulations.

Based on Functionality and Size

• Supercomputers: Most powerful, used for complex scientific calculations. Examples: Weather forecasting, cryptography, nuclear research.
• Mainframe Computers: Large, powerful systems for organizations. Used in banking, airlines, and government sectors for large-scale data processing.
• Mini Computers: Smaller than mainframes, used by small to medium businesses. Handle tasks like accounting and inventory management.
• Personal Computers: Affordable, designed for individual use. Used for personal productivity, entertainment, and communication.
• Workstations: High-performance computers for professionals (architects, engineers). Used for 3D modeling, animation, scientific visualization.
• Embedded Systems: Specialized computers within other devices (e.g., cars, appliances). Perform specific control functions.
• Mobile Devices: Portable, designed for on-the-go use. Examples: Smartphones, tablets, laptops.

Classification of Digital Computers

• Microcomputers: Also known as Personal Computers (PCs). Use a microprocessor (CPU on a single chip). Include desktops, laptops, PDAs, and tablets. Handle small volumes of data; versatile for tasks like CAD, multimedia, and workstations.
• Minicomputers: Support multiple users simultaneously. Used in organizations where departments are interconnected. Suitable for small businesses.
• Mainframe Computers: Large, powerful with high memory capacity. Process huge databases (e.g., census) at high speed. Used by big organizations, banks, and industries; support hundreds of users on a network.
• Supercomputers: Fastest and most expensive. Perform billions of instructions per second. Multiprocessor systems used for complex scientific applications like weather forecasting.

Hackers & Crackers

• Hacker: Warns users about potential malicious activities. Often aims to improve security.
• Cracker: Intentionally steals information without user knowledge. Engages in malicious activities for personal gain.

Basic Computer Operations

• Booting Up: Starting the computer and loading the operating system (OS) into memory. Includes running checks to ensure all hardware is functioning properly.
• Logging In: Entering your username and password to access your user account after booting up.
• Running Programs: Launching various programs such as web browsers, office applications, and media players.
• Accessing Data: Retrieving data stored on your computer or connected devices (e.g., external hard drives, cloud storage). Includes files, documents, photos, and media.
• Connecting to the Internet: Use a web browser to access websites, download files, and communicate online.
• Communicating with Other Devices: Interact with connected devices like printers and scanners to print documents or scan images.
• Saving and Backing Up Data: Regularly save and back up data to avoid loss. Save to local hard drives, external drives, or cloud storage.
• Shutting Down: Properly close all programs and files before shutting down the OS to ensure data is saved.
• Troubleshooting: Diagnose and resolve issues related to hardware or software, perform updates, or reinstall drivers as needed.
• Security: Keep your computer secure with antivirus software, firewalls, and other measures to protect data and prevent unauthorized access.

### Issues with Basic Computers and Computer Operations

• Slow Performance: Computers can become sluggish due to insufficient storage space, outdated hardware, or malware.
• Malware and Viruses: Malicious software can infect computers, causing problems such as data loss, system crashes, and identity theft.
• Hardware Failures: Hardware components can fail over time, resulting in system crashes, data loss, and display issues.
• Software Glitches: Software applications may malfunction or crash, leading to data loss or unresponsive programs.
• Bullying and Spreading Negativity: Social media platforms can facilitate negative behavior, including bullying and harmful comments, which have a detrimental effect on society.

Different Ways to Connect to the Internet

• Dial-Up: Connects via phone line to access the Internet. Cannot make or receive calls while connected.
• Broadband: The most popular high-speed connection. Offered by cable or phone companies.
• Wireless Connection: Includes mobile and Wi-Fi services, allowing Internet access via radio waves.
  • Wi-Fi: Provides high-speed connectivity without cables.
  • Mobile Phones: Smartphones enable Internet access through data packs without wires.
• Satellite: Used for wireless Internet in areas without broadband.
• Integrated Services Digital Network (ISDN): Allows audio and video data transmission using telephone lines.

Other Things You Can Do on the Internet

• Instant Communication: Communicate globally through email and social media platforms.
• Stay Informed: Access news updates from various sources.
• Online Shopping: Shop for goods and services from anywhere.
• Manage Finances: Handle banking and financial affairs online.
• Socialize: Meet new people and build relationships.
• Entertainment: Watch TV shows and movies online.
• Skill Enhancement: Learn new skills or take online courses.

Data Representation

• Data: Symbols representing people, events, things, or ideas.
• Data Representation: Form in which data is stored, processed, and transmitted.
• Digitization: Converting information into digital data for manipulation by devices.
• Digital Revolution: Evolved from large, expensive computers to ubiquitous digital devices.
• Bits: The basic unit of digital data, represented as 0s and 1s.
• Digital File: A named collection of data on a storage medium (e.g., hard disk, CD, flash drive).

Representing Numbers

• Numeric data: Numbers used in arithmetic operations.
• Binary System (Base 2): Digital devices use this system, where numbers are represented using 0 and 1. Example: Decimal number 2 is represented as "10" in binary.

Representing Text

• Character Data: Composed of letters, symbols, and numerals not used in calculations (e.g., name, address, hair color). Commonly referred to as "text."
• Encoding Schemes:
  • ASCII (American Standard Code for Information Interchange): Uses 7 bits for each character. Example: Uppercase "A" is represented as 1000001.
  • Extended ASCII: A superset of ASCII using 8 bits per character. Provides codes for 256 characters (e.g., "A" is 01000001).
  • Unicode: Uses 16 bits and supports 65,000 characters, accommodating multiple languages.
  • UTF-8: A variable-length encoding that uses 7 bits for ASCII characters and 16 bits for others as needed.
• Text File Formats:
  • ASCII Text Files: Unformatted and typically have a.txt extension. Apple devices label them as "Plain Text," while Windows calls them "Text Document."
  • Formatted Text: Requires embedded formatting codes for styles. Common formats:
    • DOCX: Produced by Microsoft Word.
    • PAGES: Produced by Apple Pages.
    • PDF: Produced by Adobe Acrobat.
    • HTML: Used for web pages via markup language.

Bits and Bytes

• Data Encoding: All data in digital devices is encoded as bits (binary digits).
• Byte: A group of eight bits.
• Terminology: Terms like kilo, mega, giga, and tera quantify digital data and are commonly used to describe storage capacity and network speeds.
• Usage:
  • Bits: Used for data rates (e.g., Internet speeds, download speeds).
  • Bytes: Used for file sizes and storage capacities.

Common Measurements

• Kilobyte (KB or Kbyte): 1,024 bytes. Often used for small files (e.g., 104 KB).
• Kilobit (Kb or Kbit): 1,024 bits. Used for slow data rates (e.g., 56 Kbps for dial-up connections).
• Megabit (Mb or Mbit): 1,048,576 bits. Used for faster rates (e.g., 50 Mbps for Internet connections).
• Megabyte (MB or MByte): 1,048,576 bytes. Typically used for files like photos and videos (e.g., 3.2 MB).
• Gigabit (Gb or Gbit): 1,073,741,824 bits. Used for very fast network speeds (e.g., 100 Gbit).
• Gigabyte (GB or GByte): 1,073,741,824 bytes. Commonly refers to storage capacity (e.g., 16 GB).

Data Compression

• Purpose: Reduces file size and transmission times by recoding data to contain fewer bits.
• Types of Compression:
  • Lossless Compression: Compresses data without losing any information.