Module 1: Common Computing Devices and Workstation Usage

Module 1 / Unit 1: Common Computing Devices

Objectives

• Describe the basics of how a computer processes data: Input \to Processing \to Output \to Storage.
• Describe the functions and capabilities of various computing devices: PCs, servers, mobile devices, and home automation.

Information Technology (IT) Preamble

• An Information Technology (IT) system processes, stores, and transfers information.
  • Information forms: words, numbers, pictures, sound, video.
  • All information is represented using binary digits (ones and zeros).
  • Information stored and processed this way is often called data.
• Components of an IT system: computers, telecommunications networks, other programmable electronic devices.
• ICT (Information and Communications Technology) is often preferred over IT due to the importance of communications.
• We live in an "Information Age", where the effective use of information is as defining for the 21^{st} century as the industrial revolution was before it.
• Computers and software enable faster data processing and task performance.
• IT systems are flexible and can perform a variety of tasks.
• IT networks (e.g., the global Internet) facilitate quick information distribution and sharing.

Computer Hardware and Software

• A computer is a system that manipulates data according to a set of instructions.
• Three essential elements for useful computer tasks:
  • Hardware: The devices and components making up a computer system.
    • Many parts are inside the computer's case.
    • Peripheral devices are connected externally (e.g., input devices like keyboards/mice, output devices like monitors).
  • Software: The instructions a computer follows (computer programs).
    • The Operating System (OS) establishes a basic software environment.
    • Software applications (e.g., word processors, spreadsheets) extend computer functionality and allow the same hardware to be used for various purposes.
  • Computer's User: Interacts with the software interface to control the system, input information, and create data files.

Basics of Computing and Processing

• Computer components function as interfaces.
• Input/output hardware (mouse, monitor) provide an interface between the user and the computer.
• Other interfaces exist between hardware components and software applications.
• General Processing Flow:
  • User selects a command (e.g., clicking an icon or typing).
  • Software application receives the command and, using the OS, converts it into instructions.
  • Instructions/input data are stored in system memory (commonly Random Access Memory - RAM).
  • The Central Processing Unit (CPU) retrieves and processes each instruction or data file from memory.
  • The CPU writes the result back to memory and directs other components (e.g., display subsystem to update image, storage subsystem to save data).
• All instructions and data are ultimately represented as strings of 1s and 0s (binary).
• 1s and 0s are represented as on/off states in the transistors of the CPU and RAM.
• A CPU can process billions of binary instructions per second, creating the illusion of "thinking."

Input, Output, Processing, and Storage (IOP&S)

• These four functions describe how data moves through a computer:
  • Input: Computer receives data entered by the user via peripheral devices (mice, keyboards, scanners, cameras, microphones).
  • Processing: Data is written to memory and manipulated by the CPU, based on instructions from the OS and applications.
  • Output: Processed data is shown or played to the user via an output device (monitor, loudspeaker system).
  • Storage: Data is written to persistent storage devices (hard disks, optical discs) because system memory usually only preserves data while powered on.
• Networking: A special class of input/output, or more helpfully, a separate function, allowing computers to exchange data.

Personal Computers (PC)

• The term "Personal Computer" generally refers to versions of the IBM PC, developed in 1981.
• IBM PC was based on an Intel microprocessor (CPU), also called the x86 architecture or platform.
• PCs were fundamentally different from mainframes as they were operated directly by the end-user.
• Most workstation and laptop PCs for home and office still use the IBM PC design and x86 platform.
• The PC platform became associated with Microsoft's Windows operating system.
• In recent decades, PCs have become smaller and more portable (tablets, smartphones) and can use different hardware platforms and OSs.
• The growth of the Internet and miniaturization of electronics led to the Internet of Things (IoT), where ordinary appliances gain processing and communications capabilities.

Desktop and Workstation Computers

• Housed in a case that sits on or under a desk, often called desktop PCs or desktops.
• Can be used independently by a single user to run powerful software or as a network client to access shared resources.
• Terms PC, desktop computer, and workstation are often used interchangeably, though "workstation" can imply a particularly powerful desktop.
• Components are attached to a motherboard inside the case.
• Require peripheral devices (essential: mouse, keyboard, monitor; optional: speakers, microphone, printer) connected via ports.
• Advantages of Desktops: Customizable with higher/lower specified components, making them suitable for different tasks.
• Performance Factors (a workstation-class computer with higher spec components costs more but processes data faster):
  • CPU speed: Determines basic computer speed.
  • System memory (RAM): More RAM allows running more applications simultaneously and faster processing of large data amounts.
  • Main storage drive capacity: Determines how much data is stored when the computer is off.
    • Note: Type and speed of storage drive significantly impact system speed (e.g., Solid State Drives (SSDs) are much faster than legacy hard drives).
  • Optional components: Extend functionality (e.g., sound card for audio, webcam for recording).
  • Peripherals quality: Improves user comfort (ergonomics).
  • Graphics subsystem: Also an important performance factor.
• All-in-One PCs: Computer components (excluding keyboard and mouse) are integrated within the monitor case.

Servers

• Any computer providing services to other computers; typically implies a powerful computer supporting multiple users simultaneously in a network.
• Use similar components to desktops, but they are generally more powerful, reliable, and expensive.
• Reliability is critical: If a server fails, many users can be impacted. Achieved through high-quality components and redundancy (extra copies of components) to make the system fault tolerant.
• Designed for easy expansion and upgrade.
• Often housed in special cases designed for steel rack shelving systems.
• Note: The term "server" can refer to both hardware and software (e.g., software servers include web servers, email servers, database servers, authentication servers).

Laptops

• Integrate display, system components, and input/output devices into a single, portable case (chassis).
• Distinguishing Features from Desktop PCs:
  • Size and weight: Typically between 1 and 4 kg (2-9 lbs).
  • Display type: Use flat-panel displays, built into the case (e.g., 11-14", 15-16", 17"+).
  • Input devices: Integrated keyboard, touchpad (instead of mouse), and/or touchscreen.
  • Power source: Can run from internal battery packs or building power.
  • Components: Use smaller, lighter, lower-power versions of desktop CPU, RAM, and graphics components.
  • Networking: Primarily use wireless radio technologies for network connection.
• Nomenclature: Small laptops are called notebooks and subnotebooks; larger ones are "desktop replacements".
• Ultrabook: Laptops meeting specific Intel specifications for performance, size/weight, and battery life.
• Hybrid laptops: Can function as both a laptop and a tablet.

PC and Laptop Vendors

• Most companies are Original Equipment Manufacturers (OEMs), sourcing components (CPUs, RAM) and assembling them into branded systems.
• Dominant global PC/laptop vendors: Dell, HP/Compaq, Lenovo (formerly IBM's PC division), Acer, Huawei, Samsung, Sony, Toshiba, Asus.
• Apple: Manufactures Macintosh computers using a different OS (Apple Mac OS) and hardware platform from IBM PC-compatible vendors.
• Chromebooks: Laptops running Chrome OS, primarily interfacing with Google's web apps.
• Dominant server computer vendors: Dell, HP Enterprise (HPE), Lenovo.

Mobile Devices

• PCs and laptops are increasingly being superseded by smaller or specialized devices.

Smartphones and Tablets

• Smartphones: Handheld devices with functionality similar to a personal computer (typically 4.5" to 5.7" screens).
  • Modern smartphones use touchscreen displays for ease of operation, overcoming the clumsy user interfaces of older PDAs and feature phones.
  • Phablets: Smartphones with screen sizes between 5" and 7".
• Tablets: Larger than smartphones (typically 7" to 10" screens), often used like a laptop without a keyboard, or as a slate with a touchscreen.
• Hybrid/Two-in-one Devices: Many Windows mobile devices can convert between laptop and tablet form factors (e.g., Microsoft Surface Pro with detachable keyboard, HP X360).
• Main smartphone/tablet vendors: Apple, Samsung. Others include LG, HTC, Huawei, Motorola/Lenovo, Microsoft, Nokia, Sony, Amazon.

Internet of Things (IoT) Devices

• IoT: A concept where many different types of "things" are embedded with processing and networking functionality, connecting to each other and the Internet.
• Processing and networking are enabled by small chips, allowing these "things" to range from cars and washing machines to clothing.

Home Automation

• "Smart" appliances (clocks, alarm systems, refrigerators) can be controlled over the Internet via home automation software.
• Often centered around a hub (e.g., Amazon Echo, Samsung SmartThings Hub).
• Hubs are typically controlled via voice recognition (Alexa, S Voice, Siri, Google Assistant) and smartphone apps.
• Compatibility is key: Ensuring consistency between networking/communications standards (Wi-Fi, Z-Wave, ZigBee, Bluetooth LE).
• Specific Home Automation Product Categories:
  • Thermostats: Remotely monitor and adjust HVAC controls via phone apps.
  • Security systems: Remotely monitor and control alarms, locks, lighting, videophone entry.
  • IP Cameras: Provide direct upload and sync to cloud storage for remote monitoring.
  • Home appliances: Remotely check refrigerator contents or start washing machine cycles.
  • Streaming media: Play content through smart speakers or TVs connected to the home network.

Modern Cars and Drones

• Modern Motor Vehicles: Use substantial electronics.
  • Embedded systems for engine/brake control, in-vehicle entertainment, navigation (sat-nav) using GPS (Global Positioning Systems).
  • "Black box" / event data recorder: Logs car telemetry (acceleration, braking, position).
  • Sophisticated driver-assist systems: automatic collision detection/avoidance, parking assist.
  • Ongoing experimentation with fully-automated self-driving/autonomous vehicles.
• Unmanned Aerial Vehicles (UAVs): Rapidly developing sector, from full-size fixed-wing aircraft to smaller multi-rotor hover drones.

Medical Devices

• Rapidly expanding use of electronics for remote monitoring and configuration.
• Not limited to hospitals; includes portable devices like cardiac monitors/defibrillators and insulin pumps.
• Allow remote monitoring and adjustment of dosage levels or settings by medical professionals, reducing need for patient visits.

Gaming Consoles

• Contain many components similar to a workstation (powerful CPUs, graphics processors, Ethernet, Wi-Fi).
• Web cameras and microphones often available as peripherals.
• Main difference from workstations: Designed for operation by a gaming pad (though keyboard/mouse are often options).
• Use an HD (High Definition) TV for display.
• Market dominated by: Sony (PlayStation), Microsoft (Xbox), Nintendo (Wii, Switch).
• Handheld game consoles: Nintendo's 3DS and Switch, some can connect to the Internet or other consoles.

Module 1 / Unit 2: Using a Workstation

Objectives

• Set up a computer system with regard for safety and healthy working practices and ergonomics.
• Navigate an OS and use input devices effectively.

Setting up a PC System

• Key Considerations during Installation:
  • Environment suitability: Protect from dust, dirt, heat (or extreme cold), dampness.
  • Safety: Ensure no electrical or trip hazards for user and passers-by.
  • Health: Prevent health risks associated with improper computer use (mouse, keyboard).
• Basic Setup Steps (Desktop):
  1. Check box contents, read manual, allow 30-60 minutes for components to adjust to room temperature to prevent condensation.
  2. Read manufacturer's setup and safety guidelines and plan installation accordingly.
  3. Position monitor and system unit to keep cables tidy and away from walkways. Lift heavy objects carefully (protect back). Ensure stability of objects on desk.
  4. Ensure adequate airflow around monitor, system unit, and large peripherals (printer, scanner).
  5. Check screen for excessive glare from windows/lighting; avoid direct sunlight.
  6. Adjust monitor, chair, mouse, and keyboard for comfortable user posture.
  7. Connect peripherals using appropriate, undamaged cables. Use cable management.
  8. Connect power cables from monitor, system unit, and peripherals to electrical outlets (check for damage, correct fuse rating, avoid overloading).
  9. Switch on peripherals, then the system unit (power symbol: \text{U} ).
  • Troubleshooting Power-On: Check power cable connection to wall socket and if socket is switched on.
• Setting up a Laptop:
  • Follow same basic principles (read manual, acclimatize).
  • Insert battery pack (usually clips into underside slot).
  • Connect to building power supply via AC adapter to charge battery for first use.
  • Can be used without peripherals, unlike desktops, but optional components can be plugged in.
  • Press power key (often marked with \text{U} ) to start.

Ergonomic Concepts

• Ergonomics: Study of factors affecting people's performance at work; poor environments cause health problems and decrease productivity.

Proper Keyboard and Mouse Placement

• Repetitive Strain Injury (RSI): Condition from repeated tasks using the same muscles, causing pain, numbness, tingling, prickly heat, strength loss.
• Mouse Use: Keep wrist straight, rest palm on mouse body.
• Keyboard Use: Keep forearms parallel with keyboard.
• Recommendations: Learn touch-typing, avoid bent wrists, do not hunch shoulders/bend forward, take frequent breaks to stretch or walk.
• Ergonomic Equipment: Angled keyboards and molded mice reduce strain; mouse mats smooth mouse action.

Sitting Position and Monitor Placement

• Poor sitting posture can cause back pain, especially with prolonged sitting.
• Recommendations: Take frequent breaks to stretch arms/legs.
• Monitor Adjustment: Top of monitor should be at or slightly below eye level.
• Chair Adjustment: Provide back and neck support.
• User Posture: Sit up straight, feet flat on floor, thighs parallel to floor, forearms level with desk.
• Source Documents: Use a copyholder to position source text at eye-level, not flat on the desk.

Navigating an OS (Windows 10 Example)

• Main OS Function: Provide a stable environment for software applications to work together.
• Hardware Control: OS controls access to computer hardware; applications use OS functions to access it.
• Tools: OS provides tools for hardware configuration (e.g., Windows Settings app), file management tools, and utilities (Notepad, Paint, WordPad, Calculator).
• Note: CompTIA ITF+ is vendor-neutral; focus on transferable skills rather than Windows-specific details.
• First Tasks: Sign in to Windows, start applications, use desktop features.

Signing in to Windows

1. Boot Process: Computer performs Power-On Self-Test (POST), then loads Windows. May display text/logo.
2. Lock Screen: Appears after loading. Press a key, click mouse, or swipe (touchscreen) to open sign-in prompt.
   • Enterprise/Older Windows: May require CTRL+ALT+DEL.
3. User Account: Sign-in prompt shows last user. Click icon for your account if different.
4. Password Entry: Type password (shown as black dots, case-sensitive).
5. Sign In: Click arrow button or press ENTER. Desktop loads.

• Benefits of Signing In: Saves personal desktop settings, allows access to network resources.
• Authentication: Password verifies you as the valid account owner.
• Windows Hello: Windows 10 feature for PIN, biometric sign-in (fingerprint, facial recognition) with appropriate hardware.

Using the Desktop and Taskbar

• Desktop: Contains shortcut icons for applications, folders, and files.
• Taskbar: Primarily manages open windows (applications, files); usually at the bottom, may auto-hide.
  • Can be dragged to different sides and resized if not locked.
  • "Automatically hide the taskbar in desktop mode" setting makes it disappear until cursor points at it.
• Open Applications: Each running program appears as an icon on the taskbar.
  • Click icons to switch windows.
  • ALT+TAB: Cycle through open windows.
  • Touchscreen: Swipe from left edge to cycle windows.
  • Task View button: Lists running programs (right of search box).
• Icon Shortcut Menus: Right-clicking an icon shows a context menu (e.g., close program, access recent documents, pinned items).
• Pinned Icons: For frequently used programs (email, web browser); always remain on taskbar. Open windows are highlighted.
  • Add, remove, reposition by dragging and dropping.
• Notification Area: Right-hand side of taskbar; displays time and icons for background programs (anti-virus, volume, battery, network status).
  • Icons have shortcut menus for configuration.
  • Touchscreen: Swiping in from right shows notifications.

Using the Start Screen

• Access: Click Start button on taskbar or press START key ( \box \text{w} ).
• Function: Manage apps, PC settings, launch desktop software.
• Display Modes:
  • Tablet mode: Displays in full screen (default for hybrid devices or manually selected).
  • Desktop mode: Displays as a menu.
• Displaying Apps: In tablet mode, click "All apps" icon. In desktop mode, all apps are displayed on left side of Start menu.
• Launching Applications: Type name in Start Screen search box (or Search box on taskbar) and select from results.
• App Management: Microsoft Store app for apps; Control Panel for desktop software programs.

Customizing the Start Screen and Taskbar

• Customizing Tiles (Start Screen):
  1. Select Start > All Apps, right-click app, select "Pin to Start".
  2. Right-click pinned tile for options:
     • Unpin from Start
     • Resize (Small, Medium, Large, Wide)
     • Uninstall
     • More (for Microsoft Store apps): Turn Live Tile Off, Pin to taskbar, Rate and review, Share.
     • More (for desktop applications): Pin to taskbar, Run as administrator, Open file location.
  3. Group tiles by dragging to unused area; hover to type group name.
• Configuring Taskbar and Start Menu Display: Start > Settings > Personalization > Start or Taskbar.

Using Input Devices

• Familiarity with mouse, keyboard, and touchscreen is essential.

Using a Mouse or Touchpad

• Moves cursor to select and move objects.
• Click: Point, click main mouse button once to select.
• Double-click: Click main mouse button twice to open.
  • Main mouse button can be configured for left or right hand.
  • Touchpads may have buttons or support tapping for clicks.
• Menu/Dialog Interaction: Point, click main mouse button once to select commands/buttons.
• Right-click: Click second mouse button for shortcut menu.
• Drag and Drop: Point, hold main mouse button, move to target, release.
• Scroll: Rotate scroll wheel or drag finger in touchpad scroll area.

Using a Keyboard

• Used for typing and issuing commands.
• Touch Typing: Recommended for comfort and efficiency. Use Home Row (A to F and J to ;) as base.
  • Keyboard Layouts: QWERTY (common for Latin scripts), Dvorak, Cyrillic. OS keyboard type setting is important.
• Hot Keys / Key Combinations: Navigate windows and perform commands.
  • ENTER (RETURN): Confirm command.
  • ESC: Cancel command.
  • CTRL and ALT: Used with other keys for special commands. ALT also activates application menus.
  • Menus (Windows 10): May only appear after pressing ALT key. Navigate using underlined access keys or ARROW keys.
  • TAB: Move to next pane in a window. SHIFT+TAB: Move back.
  • ARROW keys, PAGE UP / DOWN, HOME, END: Navigate icons or within text file.
  • SHIFT: Type capitals or superscript symbol. CAPS LOCK: Toggle capitalized typing.
  • SHIFT + ARROW keys: Select multiple icons.
  • NUM LOCK: Toggles numeric keypad between arrow keys and calculator keypad.
    • Laptops may have integrated keypad functions on normal keys, toggled.
  • START key ( \box \text{w} ): Display Start Screen/Menu, enable Instant Search.
  • SHORTCUT key: Display context menu for selected object.
  • Function keys (F1, F2, etc.): Perform special actions (F1 for help).
  • BACKSPACE: Deletes character to the left, returns to previous window.
  • DELETE: Erases character to the right, deletes icon.
  • FN key (Laptops): Operates laptop-specific functions (display toggle, wireless radio on/off) marked on other keys.

Using a Touchscreen

• Operated by gestures or on-screen keyboard.
• Basic Windows 10 Gestures:
  • Tap: Single press, equivalent to left mouse click.
  • Tap and hold: Equivalent to right-mouse click (e.g., open context menu). Can also be two-finger tap.
  • Pinch and stretch: Two fingers together to zoom in (pinch), apart to zoom out (stretch).
  • Swipe: From screen edge for specific actions (e.g., from right for notifications). Within apps, custom actions (page navigation, refresh).
  • Most touchpads also support gestures.

Recognizing Desktop Icons

• Pictures representing folders, files, and system objects.
• Main Types of Icons:
  • File (or document) icons: Show application used to edit the file (text, pictures, music).
  • Shortcut icons ( \searrow ): Links to a file; have an arrow superimposed. Deleting a shortcut does not delete the original file.
    • Shortcuts in Start Menu/Screen, or on desktop.
  • Folder icons: Organize files; indicate contents (documents, pictures, subfolders).
  • Application icons: Contain the program itself (e.g., Word program file icon differs from Word document file icon).
  • Device icons: Hard disk drives, removable drives (optical, USB), printers, medical devices, other connected devices.
    • Windows can display vendor-specific icons downloaded from the Internet.

Working with Windows

• Every desktop application runs in a window; multiple windows can be open and switched between.
• Common Window Features:
  • Panes: Some windows split into multiple panes; navigate with TAB and SHIFT+TAB.
  • Scroll bar: Appears if window not large enough to display contents; click arrows or drag button to scroll.
  • Application Controls: Toolbars and/or menu bar at top.
    • Microsoft prefers "ribbon" (combines menu bar and toolbar).
    • Menu bar may only show if ALT key is pressed.
  • Status bar: Shows useful information about selected items.
• Window Sizing and Movement:
  • Maximize / Restore button: Fill whole desktop or occupy part.
  • Resize: Click-and-drag window's border.
  • Move: Click-and-drag the title bar.
  • Arrange: Right-clicking taskbar offers options for arranging windows.
• Minimize button: Hides window from desktop; reactivate by clicking taskbar icon.
  • Use taskbar to switch between windows.
• "Shake": Drag a window to quickly minimize all other windows; shake again to restore.
• "Snap": Drag to screen edge to snap to appropriate size (e.g., half-screen).
• Resource Management: Running many programs consumes memory, slowing computer. Close unused windows to free resources.
• Closing a Window: Select "Close" or "Exit" from File menu, click Close button ( \text{X} ), or press ALT+F4.

Module 1 / Unit 3: Using an OS

Objectives

• Distinguish between different types of operating systems (workstations, servers, mobiles, embedded systems, virtualization).
• Identify common commercial and open source OSs (Windows, macOS, iOS, Linux, Chrome, Android).
• Use a browser to view websites.

Functions of an Operating System (OS)

• A computer requires an OS to function.
• Provides Interfaces: Between hardware, application programs, and the user.
• Handles Basic System Functions: Interaction with hardware and input/output.

Interface Between User and Computer (Shell)

• One basic function: provide a shell (user interface).
• Earliest OS (e.g., Microsoft's DOS): Used a command-line interface (CLI) or simple menu systems.
• Windows and later applications: Marked by Graphical User Interface (GUI), making computers easier for non-technical users.
  • Windows is sometimes described as a WIMP (Window, Icon, Menu, Pointing device) interface.
• An OS may have multiple shells (e.g., graphical shell, command line shell).
• Shells allow users to configure hardware, install/manage software, and access programs/files.

Interface Between Applications and Hardware

• Another function: "drive" computer hardware.
• OS Structure: Built from a kernel (core functions) with additional driver software and system utility applications.
• Drivers: Each hardware component requires a driver to work.
• OS Responsibility: Identify installed components and load drivers to enable their configuration and use.
• CPU Instruction Size: Computers and software can be 32-bit or 64-bit.
  • 64-bit CPUs: Can run 64-bit OS with 64-bit and/or 32-bit applications, or a 32-bit OS with 32-bit applications.
  • 32-bit CPUs: Cannot run 64-bit OS or applications.
  • 64-bit mode addresses more memory.
• Common Application Environment: OS provides an environment for different software applications.
  • Developers can focus on application functions instead of writing routines for hardware access.
  • Results in fewer OSs (high development cost).
  • OS changes must maintain compatibility with older software/hardware; eventually, legacy software may not work.

System Health and Functionality

• OS includes kernel and driver files for hardware interaction.
• Ships with utility software to configure and monitor the computer.
• Monitoring Tools: Logs record system events, trigger alerts.
• Performance Monitoring: Identify overworked components (requiring upgrade) or faulty software/drivers.

Data Management

• Utility software provides interface between user and storage devices.
• Files: Information stored as files (executable, configuration, data).
• Persistent Storage: Files saved to hard disks or other persistent storage.
• Directory (Folder) Structure: OS creates directories to organize files on storage devices.
• File Management Tools: OS provides tools to create directories, move/copy files between them.

Types of Operating System

• OS types support different commercial models and devices.

Workstation, Server, and Mobile Device OS

• Workstation OS: Runs traditional desktop PCs or laptops (e.g., Microsoft Windows, Apple OS X/macOS, Linux, Chrome OS).
  • Market Sections:
    • Enterprise client: For clients in business networks.
    • Network Operating System (NOS) / Server OS: Runs on servers in business networks.
    • Home client: For standalone or workgroup PCs in home/small office; supports basic peer-to-peer services.
• Mobile Device OS: For handheld devices (smartphones, tablets) (e.g., Apple iOS, Android).
  • Unlike workstation OSs, mobile OSs typically cannot be uninstalled and replaced; devices run the OS they were designed for.
• Server OS (e.g., Windows Server, Linux, UNIX): Often based on similar code to workstation equivalents (e.g., Windows 10 and Server 2016).
  • Includes software packages (roles) to run network services.
  • Different licensing to support more users.
  • Likely has a simpler CLI than GUI for better security and reliability.

Open Source versus Commercial

• Commercial OS: User must purchase a license to install/use. Programming code is confidential (e.g., Microsoft Windows, Apple macOS, Apple iOS).
  • Users rely on vendor for modifications.
• Open Source OS: Programming code is freely available.
  • Doesn't necessarily mean free, but developers can make changes if they make their changes available in turn.
  • Claims to offer faster, more cost-effective software improvements.
  • Examples: UNIX, Linux, Android.

Embedded OS

• Embedded System: Computer/appliance designed for a very specific function.
  • Examples: Microcontroller in IV drip meter, industrial control system, home automation hubs, smart TVs, gaming consoles.
  • OS that ships with these devices usually cannot be changed (unlike general-purpose systems).
  • May allow app installation, peripheral additions, network configuration (more scope for modification than industrial embedded systems).
• Environment: Typically static, unlike dynamic PCs where users frequently add/remove programs/data/hardware.
• Real Time Operating Systems (RTOS): Used where response times must be predictable within microsecond tolerances (e.g., drip meters, flow valves).
  • Designed for stability and reliability, cannot tolerate reboots or crashes.

Firmware

• In embedded systems, the embedded OS acts as firmware, providing all device hardware interaction.
  • Firmware is not designed for continuous change, updates are infrequent.
• PC Firmware: Workstations, laptops, servers use firmware for a low-level interface, allowing the OS to load and control components.
  • Basic Input/Output System (BIOS): Industry standard firmware; operates essential PC components, ensures PC compatibility for motherboards.
  • Unified Extensible Firmware Interface (UEFI): Newer firmware.
    • Supports 64-bit CPU operation at boot.
    • Provides full GUI and mouse operation at boot.
    • Offers better boot security.
    • May support booting in legacy BIOS mode.
• Other Devices: PC system components (graphics adapters, storage, network controllers), most peripheral devices, and network devices (routers, wireless access points) also contain their own firmware.

Virtualization

• Definition: Multiple operating systems can be installed and run simultaneously on a single physical computer.
  • Historically, one computer ran one OS at a time.
• Virtual Platform Components:
  • Computer(s) / Host: The physical machine providing resources (CPU, memory) for the virtual environment.
  • Hypervisor / Virtual Machine Monitor (VMM): Manages the virtual machine environment and facilitates interaction with host hardware/network.
    • Type I (bare metal) hypervisor: Installed directly on the computer hardware (e.g., VMware ESXi, Microsoft Hyper-V).
    • Type II hypervisor: Runs as a software application within a host operating system (e.g., Oracle VirtualBox, VMware Workstation). Host OS retains direct control of hardware.
  • Guest operating systems / Virtual Machines (VM): OSs installed under the virtual environment.
    • Number limited by hardware capacity; hypervisor may restrict OS types.
    • Each VM "thinks" it's working with normal hardware components.
    • VMs can be networked together; direct data sharing through hypervisor is rare for security.
• Uses of Desktop Virtualization: Utilizes hardware more efficiently.
  • Virtual labs: Analyze malware safely within isolated guest OSs, preventing host/network infection.
  • Support legacy software: Run old OS as a VM for applications incompatible with new host OS.
  • Development environment: Test applications under different OSs and resource constraints.
  • Training: Create isolated lab environments for students to practice without impacting production systems; VM changes can be discarded.
• Bundled with Windows 10 Professional/Enterprise: Hyper-V.
• Third-party products: VMware, VirtualBox.

Microsoft Windows

• Dominant commercial workstation OS: Estimated on 90\% of desktops/laptops.
• Windows Server OS is widely used on PC servers.
• Versions: Released periodically; historically, new versions required purchase (with upgrade discounts).
  • New versions introduce UI changes, new features, hardware support.
  • May have compatibility issues with older hardware/software.
• Windows 10 (released 2015): Current version. Microsoft adopted "Windows as a service" model, providing periodic feature updates instead of new versions.
  • Feature updates: Identified by name and number (e.g., Windows 10 Anniversary Update, 1607; Spring Creators Update, 1803).
  • Quality updates: More frequent, usually minor changes, may include small new features. Less likely to cause compatibility issues than feature updates.
  • Aims for consistent user experience across desktop PCs, laptops, tablets, smartphones.
• Older Windows Versions:
  • Windows 8 (2012) / 8.1 (2013): Introduced touchscreen UI changes, unpopular with Windows 7 users. Windows 10 was a free upgrade, quickly replaced Win 8.
    • Windows 8.1 addressed some issues with Windows 8 native UI.
    • No Windows 9 existed.
  • Windows 7 (2009): Still widely used (~45\% market share).
  • Windows Vista (2007): Never achieved significant market share.
  • Windows XP (2001): Still installed on ~5\% of devices despite no official support.
• Windows Editions: Used by Microsoft to segment markets.
  • Windows 7 Editions: Home Basic, Home Premium, Professional, Enterprise, Ultimate.
  • Windows 10 Editions:
    • Home: For domestic/SOHO use; cannot join corporate Windows domain.
    • Pro: For small/medium businesses; includes networking/management features for administrators.
    • Enterprise / Enterprise (Long Term Servicing Channel): For large enterprises (via licensing).
    • Education / Pro Education: Variants for schools/colleges (via licensing).
• 64-bit Windows (x64):
  • 64-bit Windows editions can run most 32-bit applications (check vendor).
  • 32-bit Windows cannot run 64-bit applications.
  • 64-bit Windows requires 64-bit Microsoft-signed hardware device drivers.
• Windows 10 Mobile: Microsoft's mobile OS (previous: Windows CE, Phone 7, Phone 8); adopted consistent UI/code base across devices. Very small market share compared to Android/iOS.

Apple macOS and iOS

• History: Apple Macintosh (Mac) introduced in 1984 with a GUI, contrasting IBM PC's DOS CLI.
  • Mac never matched Windows' user base but has a devoted following.

Apple Mac OS / OS X / macOS

• Exclusivity: OS only supplied with Apple-built computers; cannot be installed on ordinary PCs. Improves stability but limits hardware choice.
• Development: Current macOS (OS X) re-developed from UNIX kernel.
  • Supplemented with code for graphical interface, system utilities, and compatibility with older Mac OS apps.
• Updates: Periodic "dot" version updates (e.g., 10.13 "High Sierra"). Updates are free for existing customers.

Apple iOS

• Operating System: For Apple iPhone smartphones and iPad tablets.
• Updates: New versions released annually with .x updates (e.g., version 11, 12).
  • Free updates, but older hardware may not support all features or be supported at all.
• Nature: Derived from UNIX (via macOS), but is a closed source operating system.
  • Code is confidential; only Apple can modify it.
• Popularity: Due to ease of navigation.
  • Interface: Primarily touch-controlled.
  • External Button: Only Home key (returns to Home Screen/Desktop), besides volume and power.
  • Gestures: Tap (left click), tap and hold (right click), swipe/flick (access keyboard, search), double-click Home to open Multitasking bar.
  • Stylus support: Special soft-touch stylus.
  • Other input: External keyboards, Siri (voice recognition/personal assistant).

Linux, Chrome, and Android

• Linux: Originally developed by Linus Torvalds, based on the UNIX operating system.
  • UNIX: Developed over 30+ years by various organizations; several versions (some incompatible, proprietary, copyrighted).
  • Linux: Developed as a fully open source alternative to UNIX (and Windows, macOS, iOS).
• Uses: Can be a desktop or server OS.
• Distributions (distros): Many exist (SUSE, Red Hat, Fedora, Debian, Ubuntu, Mint).
  • Each distro adds specific packages, interfaces to the generic Linux Kernel, and support options.
  • Does not require a graphical interface, but most provide one.
• Commercial Applications: IBM, Sun/Oracle, Novell develop end-user apps for Linux.
• Deployment: Used more in schools/universities than business/home as a desktop OS.
  • Very widely deployed on web servers.

Chrome OS

• Derived from Linux: Via open source Chromium OS.
• Nature: Chrome OS itself is proprietary.
• Hardware: Developed by Google to run on specific budget laptop (Chromebook) and PC (Chromebox) hardware.
• Primary Use: Designed for web applications (software hosted on Internet server, client connects via browser).
  • Client computer doesn't need to be powerful as server does most processing.
• Environment: Minimal compared to Windows; less chance of software/driver interference with browser function.
• Apps: Supports "packaged" apps for offline use and Android apps.

Android

• Operating System: Smartphone/tablet OS developed by the Open Handset Alliance (primarily Google).
• Nature: Open-source OS, based on Linux. Software code made publicly available (source.android.com).
• Vendor Customization: Greater scope for hardware vendors (Acer, Asus, HTC, Huawei, LG, Motorola, OnePlus, Oppo, Samsung, Sony, Xiaomi) to produce vendor-specific versions.
• Updates: New major (1.x) and minor (x.1) versions (e.g., 7.1 Nougat, 8.1 Oreo).
  • Device compatibility for new versions is more mixed than iOS due to vendor-specific editions.