Lecture 2 Computing-Systems-and-Components

Page 1: Introduction

• HO TECHNICAL UNIVERSITY

• Department of Computer Science

• Course: HOTU 103/CLT 112 - Computer Literacy

• Instructor: Prince Modey

Page 2: Overview of Computing Systems and Components

• Focus on fundamental building blocks of computing systems.

• Covers:

  • Different types of computers.

  • Essential hardware components.

  • Overview of software and databases.

Page 3: Types of Computers

• Desktop:

  • Powerful, stationary computers for general-purpose tasks.

• Laptop:

  • Portable computers with integrated displays and keyboards.

• Mobile Devices:

  • Handheld devices such as smartphones and tablets.

• Servers:

  • Powerful computers designed for multiple users/applications.

Page 4: Central Processing Unit (CPU)

• The CPU is the brain of the computer.

• Responsible for executing instructions and processing data.

Page 5: Random Access Memory (RAM)

• Temporary storage for data and programs currently in use by the CPU.

Page 6: Storage Devices

• Provide long-term storage for data/programs.

• Types include:

  • Hard drives

  • Solid State Drives (SSDs)

  • Flash drives

Page 7: File Compression

• Two techniques for data compression:

  • Lossy Compression:

    • Certain loss of accuracy, high degree of compression (1:10 to 1:50).

    • Commonly used for graphic files and digital voice files.

  • Lossless Compression:

    • Generates an exact duplicate, lower degree of compression (1:4).

    • Used for databases, spreadsheets, and documents.

Page 8: Backup

• The process of creating duplicate copies of information.

• Types of backups include:

  • Full Backup:

    • Backs up all selected data.

  • Differential Backup:

    • Backs up only the data that has changed since the last full backup.

  • Incremental Backup:

    • Backs up only data changed since the last backup of any type.

Page 9: Full Backup

• Contains all data in selected folders and files.

• Serves as the base for subsequent backups.

Page 10: Disk Defragmentation

• Consolidation of fragmented data on a volume.

• Fragmentation occurs over time due to file operations.

• Disk Defragmenter helps improve efficiency by rearranging data.

Page 11: The Importance of Disk Defragmentation

• As fragmentation increases, computer performance may decrease due to inefficient data retrieval.

• The Disk Defragmenter tool re-organizes fragmented data to enhance efficiency.

Page 12: Data Recovery

• Data Recovery Utility:

  • Used to restore physically damaged data.

• Data can be damaged by:

  • Viruses, bad software, hardware failures, or power fluctuations.

Page 13: File Compression (Overview)

• The process of reducing the file size.

• Works by eliminating redundancy and unnecessary data.

• Different compression formats, including:

  • WinZip (.zip)

  • WinRAR

Page 14: Input/Output Devices

• Input devices allow users to interact with the computer.

• Output devices display or provide information generated by the computer.

Page 15: Input Devices Overview

• Defined as hardware that allows users to input data into a computer system.

• Examples include:

  • Keyboard

  • Mouse

  • Scanners

Page 16: Types of Input Devices

• Keyboard:

  • Converts characters to electrical signals.

• Pointing Devices:

  • Includes mice, trackballs, joysticks, touchpads, etc.

• Source Data Entry Devices:

  • Such as scanners (barcode readers, fax machines, imaging systems).

Page 17: More Input Devices

• Touchpad:

  • Detects fingertip movement to control cursor on laptop screens.

• Trackball:

  • Mouse alternative with a ball on top for navigation.

Page 18: Joysticks and Scanners

• Joysticks:

  • Used primarily for gaming.

• Scanners:

  • Convert printed materials to digital format, can use OCR for text.

Page 19: Multimedia Input Devices

• Webcam:

  • Used for live images via the internet.

• Digital Cameras:

  • Store images on memory cards.

• Microphone:

  • Converts speech to text using specialized software.

Page 20: Keyboard Design and Function

• Keyboards are essential input devices consisting of various buttons (keys).

• Different layouts include QWERTY and Dvorak.

Page 21: QWERTY Keyboards

• Widely used, named after the first six letters on the top row.

Page 22: Dvorak Keyboards

• Designed for speed with frequently used keys located near typical finger positions.

• Less common, many prefer QWERTY despite Dvorak's logical structure.

Page 23: Keyboard Variants

• Traditional Keyboards:

  • Standard full-sized and rigid design.

Page 24: Flexible Keyboards

• Designed for mobile users; can be rolled or folded.

Page 25: Ergonomic Keyboards

• Focus on comfort with unique designs that reduce wrist strain.

Page 26: Wireless Keyboards

• Battery-powered, using wireless technology (e.g., infrared) for connectivity.

Page 27: Mouse Overview

• Common pointing device enabling interaction with GUI.

• Variants include features like scrolling wheels.

Page 28: Mechanical Mouse

• Uses a ball for movement sensing; often requires a mouse pad.

Page 29: Optical Mouse

• Senses movement with light; preferred for precision and flexibility.

Page 30: Wireless Mouse

• Functions similarly to wired mice but operates without cables.

Page 31: Scanning Devices

• Convert text and images into digital forms; include:

  • Optical scanners, barcode readers, and character recognition devices.

Page 32: Flatbed Scanners

• Documents placed on a glass surface for scanning (similar to a photocopier).

Page 33: Portable Scanners

• Handheld devices that slide across the material to scan it directly.

Page 34: Barcode Readers

• Translates barcodes into digital data for pricing and inventory.

Page 35: Output Devices Overview

• Used to produce output from processed data.

• Common types:

  • Monitors

  • Printers

  • Speakers

Page 36: Types of Output

• Softcopy:

  • Displayed on screens (intangible).

• Hardcopy:

  • Printed output (tangible).

Page 37: Monitors

• Displays signals from a computer; comes in CRT and flat-panel types.

Page 38: Monitor Features

• Comprised of pixels; resolution affects image clarity.

Page 39: Software

• Provides instructions for hardware operations; includes:

  • Operating systems

  • Applications

  • Utilities

Page 40: Databases

• Organized collections of data for efficient access and management.

Page 41: Database Fundamentals

• Key definitions and components of databases as referenced in Chapter 1 of "Fundamentals of Database Systems" by Elmasri and Navathe.

Page 42: Definitions of Database

• Organized collections of logically related data.

• Shared data for various users' needs.

Page 43: Database Application Examples

• Everyday uses such as supermarket transactions, credit card purchases, and insurance applications.

Page 44: Data Definitions

• Data: Representations of objects/events.

• Information: Processed data for knowledge gain.

• Metadata: Descriptive data about other data.

Page 45: What is a Database?

• Shared collection of logically related data designed for organizational needs.

Page 46: Data Context

• Contextual understanding enhances data usability (e.g., course rosters).

Page 47: Data Presentation

• Graphical displays convert data into actionable information for decision-making.

Page 48: Data Properties

• Descriptions of data characteristics, including types, sizes, and values.

Page 49: Organizational Database Concept

• Highlights inter-departmental relationships within an organization.

Page 50: Historical Context of Computers

• Initially used for computational purposes; commercial applications expanded functionalities.

Page 51: File Processing System Overview

• Programs perform services with individual data management responsibilities.

Page 52: Registration Applications

• Registration data management structures for educational institutions.

Page 53: Example Data Structures

• Includes attributes like names, registration numbers, and contact details within systems.

Page 54: File-Based Processing

• Outlines the stages of data entry and transaction processing.

Page 55: Disadvantages of File Processing

• Issues include data dependence, redundancy, limited sharing, and inconsistent data.

Page 56: Project Disadvantages

• Challenges in development timelines, maintenance, and potential data inconsistencies.

Page 57: Data Dependence Problems

• Concerns about the need for each application to manage its metadata and processes separately.

Page 58: Data Redundancy Problems

• Issues surrounding duplicate data causing integrity issues.

Page 59: Solution: Database Approach

• Centralized management and organization of data for streamlined access.

Page 60: Advantages of Database Approach

• Benefits include improved sharing, independence, controlled redundancy, and integrity.

Page 61: Database Management System (DBMS)

• Software for creating and maintaining databases; handles user access through requests.

Page 62: DBMS Operational Concept

• Demonstrates integration of various departments within an organizational database.

Page 63: Key Takeaways

1. Components of computing systems include hardware and software.

2. Different computer types serve specific functions.

3. Software organizes and manages data via databases.

Page 64: Next Steps

• Explore further into computing systems to deepen understanding.

Page 65: Conclusion

• The end of the presentation.