Introduction to Computer Hardware

Introduction

• Computer: A high-speed electronic device that processes data, produces output, and stores information in memory.
• Basic computer operations: Input, processing, and output.
• Computers understand machine language (0s and 1s), which is not understandable by humans.
• Characteristics of computers: Accuracy, repetitive work, and tireless operation.

Computer Hardware

• Physical components of a computer system.
• Four categories:
  • Input devices: Receive raw data.
  • Processing devices: Process data into information.
  • Output devices: Display or distribute data and information.
  • Storage devices: Store data and information.

Input Devices

• Keyboard: Most common input device, similar to a typewriter with additional keys.
  • Typing keys: Alphabets (A-Z) and numbers (0-9).
  • Function keys: 12 keys with specific functions.
  • Control keys: Cursor and screen control (arrow keys, page up/down, control, alternate, escape, home, end, insert, delete).
  • Operator and special character keys: Symbols and punctuation.
  • Special purpose keys: Enter, backspace, num lock, caps lock, shift, space bar, tab, scroll lock, sleep, print screen.
  • Numeric keypad: Quick access to numbers, arrow keys, and operator keys.
• Mouse: Popular pointing, selection, and cursor control device.
• Microphone: Records sound and stores it in digital format, used for multimedia.
• Joystick: Pointing device for moving the cursor, mainly used in games.
• Light pen: Similar to a pen, used for selecting menu items or drawing on the screen.
• Scanner: Transfers information from paper into digital format, similar to a photocopy machine.
• Barcode reader: Reads barcoded data using light and dark lines, common for labeling and numbering items.
• Optical Character Reader (OCR): Scans printed text optically, converting it into readable text and storing it in computer memory.
• Magnetic Ink Character Reader (MICR): Used in banks to read code numbers and check numbers printed with special ink.
• Optical Mark Reader (OMR): Scans marked answer sheets, specifically for multiple-choice exams.

Output Devices

• Monitor: Most common output device, similar to a TV, available in different sizes and resolutions.
  • Monitor Resolution: Describes the visual dimensions of a display in width and height, measured in pixels.
  • CRT (Cathode Ray Tube): Uses phosphorescent dots for generating pixels, bulky and heavy.
  • Flat panel screen: Uses liquid crystals or plasma for producing output, more compact and efficient.
    • LCD (Liquid Crystal Display): Light passes through liquid crystals for pixel generation.
    • LED (Light Emitting Diodes): Use light emitting diodes for pixel generation.
• Printer: Generates hard copies of documents and images on paper.
  • Impact printer: Prints through direct contact between an ink ribbon and paper.
  • Non-impact printer: Uses laser, electrostatic, chemical, or inkjet technologies for printing.
• Headset: Combines speakers and a microphone, commonly used for gaming, video conferencing, and online meetings.
• Projector: Projects a computer generated image onto a surface, ideal for presentations and viewing videos.
• Plotter: Creates hard copies of digitally designed drawings, mainly used by architects and engineers.

Motherboard - The Heart of the Computer

• Essential part connecting all computer components, both internal and external.
• Contains various slots and ports for connecting components.

Microprocessor (CPU)

• The control center of the computer, processing instructions and data.
• Located on the motherboard, a single integrated chip with billions of components.
• Performs all arithmetic and logical operations, acting as the computer's 'brain'.

Storage Devices

• RAM (Random Access Memory): Primary memory, fast solid-state storage medium accessible by the CPU for open programs and files; volatile—data lost when power is off.
• ROM (Read Only Memory): Permanent primary storage containing essential programming for computer startup (boot up).
  • Contains BIOS (Basic Input/Output System) chip, located on the motherboard.
  • Holds programs or software instructions for essential tasks.
• Hard Disk Drives (HDD): Non-volatile, magnetic secondary storage devices with large capacity (gigabytes or terabytes).
  • Two types: Internal and external.
  • Used in desktops, laptops, TV recorders, servers, and mainframes.
• Solid State Drive (SSD): Non-volatile secondary storage device using flash memories; no moving parts, faster than HDDs; more expensive.
  • Used in high-end PCs, laptops, smartphones, tablets.
• Flash storage devices: Non-volatile, solid-state secondary storage devices using flash memory, for portability and various capacities.
  • Pen drive: Used in computers.
  • Memory cards: Used in cameras, mobile phones, tablets.
• CD, DVD, Blu-Ray: Optical secondary storage disks, storing data as changes in the disk surface.
  • CD capacity: 700 megabytes.
  • DVD capacity: 4.7 gigabytes.
  • Blu-Ray capacity: 25 gigabytes to 128 gigabytes.
• Optical disk drive: Reads, writes, and rewrites data on optical disks using laser technology.
  • CD, DVD, Blu-Ray drives: Common types, available as internal and external versions.

Motherboard Components (Slots and Ports)

• CPU slot (processor socket): Connects the microprocessor (CPU) to the motherboard.
• CPU fan: Placed above the processor for cooling.
• RAM slots: Connect RAM chips to the motherboard.
• PCI slot (Peripheral Component Interface): For inserting expansion cards (network, sound, modems, video).
• AGP slot (Accelerated Graphics Port): High-speed communication channel for video cards.
• SATA (Serial Advanced Technology Attachment) port: Connects hard drives and DVD drives.
• IDE (Integrated Drive Electronics) port: Connects older hard drives and CD drives.
• Floppy controller: Connects floppy drive.
• CMOS battery: Powers BIOS settings even when power is off.
• PS/2 port: For connecting keyboards and mice.
• USB (Universal Serial Bus) port: Connects many devices (mice, keyboards, scanners, cameras, printers, storage).
• Parallel connector: For older printers.
• Serial connector (COM port): For older serial devices.
• VGA (Video Graphics Array) port: Connects a monitor.
• Line out jack: Speakers or headphones.
• Line in jack: Computer audio to stereo system.
• HDMI (High Definition Multimedia Interface) port: High-quality audio and video.
• Game port: Joysticks, midi keyboards.
• Network/Ethernet port: Connects to a network.
• SCSI (Small Computer System Interface) port: Connects hard drives to older computers.

Power Supply Unit (PSU)

• SMPS (Switching Mode Power Supply): Converts electrical power from AC to DC for computer components.
• Connectors: Power the motherboard, hard drives, and other parts.

Conclusion

• Understanding the basic components and functions of a computer system is crucial for basic computer use, troubleshooting, and upgrading.