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Operating System Basics - Comprehensive BSIT Notes

Learning Outcomes

  • Understand the types of operating systems available
  • Differentiate among the major desktop operating systems
  • Explain how device drivers work
  • Explain computer file storage concepts

System Software

  • System software comprises core components that support the computer’s operation, including BIOS and OS utilities.
  • BIOS (Basic Input/Output System)
    • Stored on a ROM BIOS chip on the motherboard
    • Referred to as and described as “Firmware” — both hardware and software
    • Starts up the computer at a low level, before the OS loads
  • Operating System Utilities
    • Utilities are built-in tools and programs that assist the OS in managing hardware and software

BIOS and Firmware Details

  • BIOS is a foundational layer used to initialize hardware and bootstrap the OS
  • Firmware includes both hardware firmware and software components embedded in hardware
  • The BIOS runs before the OS to perform POST (power-on self-test) and hardware initialization

OS Functions and Roles

  • The operating system provides the user interface
  • It communicates with the hardware
  • It runs applications
  • It manages files and storage

Platform Architectures

  • OS Platform: the hardware environment required to run a particular operating system
  • Intel platform (IBM-compatible)
    • Windows, DOS, UNIX, Linux
  • Macintosh platform
    • Mac OS X
  • iPad/iPhone platform
    • iOS

Interface Types

  • Graphical User Interface (GUI)
    • Icons, windows, menus, and a point-and-click interaction model
    • Example elements shown in operating system graphics (e.g., Recycle Bin, icons, program icons, etc.)
  • Command-line interface (CLI)
    • Text-based interface for issuing commands

Desktop and Notebook Operating Systems

  • Windows
    • Best known, widest selection of applications
  • Mac OS
    • User-friendly, runs on Mac hardware; broad application availability
  • Linux
    • Free and open-source; can be more challenging to configure; fewer applications by default, but growing

Mac OS X Mavericks (Example UI Context)

  • Mac OS X Mavericks is an example of a Mac OS X release shown with standard menu options (File, Edit, View, Window, Help) and a GUI-focused desktop environment
  • Darwin-related background is part of the Mac OS X lineage; emphasis on a graphical environment and system tools

Windows Desktop Experience (Illustrative Example)

  • Windows 7 as an example of a desktop OS with a traditional Start Menu, taskbar, and desktop icons
  • Typical desktop software suite includes Internet Explorer, Word/Excel/PowerPoint, Notepad, Calculator, etc.

Linux Desktop Environments (Ubuntu Example)

  • Ubuntu Linux (example shown)
    • Desktop environment with Activities overview and a panel of commonly used apps
    • Included apps in the transcript: Rhythmbox (music), Shotwell (photo manager), Thunderbird Mail, Transmission (bit-torrent client), GNU tools and utilities
    • Settings and Software Updater for system maintenance

Chrome OS

  • Google Chrome OS is shown as a lightweight OS focused on web applications and Google services
  • Integrates with Google tools such as Gmail, Drive, Docs, Sheets, Slides, YouTube, and Play Store

Server Operating Systems

  • Windows Server
    • Familiar GUI interface for those experienced with Windows
    • Provides server-oriented tools (Server Manager, PowerShell, Administrative Tools)
  • UNIX
    • Mature server capabilities with time-tested stability; strong command-line heritage
  • Linux (Server variants)
    • Free, customizable, numerous services and utilities available

UNIX Desktop/Command-Line Context (Example Commands)

  • UNIX-like systems often emphasize a command-line interface and scriptable tasks
  • Example system-level commands or observations shown included shell prompts and /etc/fstab usage
  • Common concepts observed
    • Mounting/partitioning devices via /dev entries and fstab
    • System and user commands for networking, date/time, and process management

iOS and Mobile OS Contexts

  • iOS on the iPad (iPad interface shown with app icons and system tray)
  • Windows Phone OS (mobile OS context shown with device UI elements)

Windows Device Drivers

  • Device Drivers
    • Translate OS requests into the language understood by the hardware device
    • Translate messages from the device back to the OS
    • Published by the device manufacturer for a specific OS and device model
    • Driver updates are periodically released to fix bugs and improve performance

Device Manager (Windows Control Panel)

  • Accessed from the Control Panel (System section)
  • Shows installed devices and details for drivers (including versions)

Digital Storage Vocabulary

  • Drive: physical storage device
  • Volume: a lettered section of a storage device (a logical drive)
  • Partition: division of a physical drive into logical volumes
  • Format: creating a filesystem on a volume

File Systems

  • File system: storage system used to store and organize files on a volume
  • Common file systems include:
    • NTFS: Windows hard drives (Windows 2000 and higher)
    • HFS+: Mac OS X hard drives
    • ISO 9660 or UDF: CDs and DVDs
    • FAT32: Windows 95/98/Millennium Edition hard drives

Disk Management (Windows)

  • Access via Administrative Tools in Control Panel
  • Visualizes disks, volumes, and file systems
  • Disk types and statuses shown (e.g., NTFS, UDF, etc.)
  • Example components observed:
    • OS volume: (C:) with NTFS
    • Recovery and other partitions with various file systems
    • DVD/CD-ROM drives and unallocated space
  • Disk Management helps with layout, health status, and capacity planning

File Paths and Root/Folder Structure

  • Root directory = top-level folder in a drive
  • Path format example: the complete descriptor of a file’s location, including the volume and folders
  • Example path: E:\Budget\January.txt
  • Path navigation is represented graphically in folder trees and navigation panes (Windows Explorer)

File Paths and Folder Tree (Windows Explorer)

  • Folder tree in the navigation pane shows a graphical representation of the folder system
  • Helps users locate files quickly within volumes and directories

File Extensions and Types

  • Extension: characters after the period in a file name that indicate the file’s type
  • Extensions tell the OS which application to use to open a data file
  • Extensions indicate whether a file is executable (e.g., .exe, .com) or data
  • Common extensions and types include:
    • txt: Text
    • gif, png, jpg, tif: Photo or graphic
    • doc, docx, docm: Word processing document
    • rtf: Rich Text Format document
    • xls, xlsx, slxm: Spreadsheet
    • ppt, pptx, pptm: Presentation
    • mdb, accdb: Database (Microsoft Access)
    • pdf: Portable document format
    • xps: XML Paper Specification document
    • exe, com, bat: Executable programs
    • dll, ini, dat: Helper/data files
    • zip: Compressed archive
  • Notes on usage:
    • Some programs support multiple extensions
    • Some extensions map to multiple related applications depending on the OS

File Compression and NTFS Compression

  • ZIP files
    • Can compress individual files, groups of files, or folders into a single archive
    • To create: right-click a group of selected files, choose Send To → Compressed (zipped) folder
  • NTFS compression
    • Apply to individual files or folders to save disk space
    • Occurs transparently to the user; compression flag is associated with the folder/file

File Encryption

  • Protects files from unauthorized access
  • NTFS encryption
    • Only the user who encrypted the files can view them on the local volume
  • BitLocker encryption
    • Encrypts the entire drive so data cannot be read if removed from the computer

Backup Vocabulary and Practices

  • Archive attribute: file attribute indicating whether a file has changed since its last backup
  • Full backup: backs up all files and sets their archive attribute to Off
  • Differential backup: backs up all files with the archive attribute On but does not change that attribute
  • Incremental backup: backs up all files with the archive attribute On and then sets it to Off

Summary / Study Prompts

1) List three types of system software.
2) What is the difference between an OS and a platform?
3) List five types of utility programs.
4) List three operating systems that would run on an IBM-compatible desktop PC.
5) Name three operating systems used on smartphones.
6) Explain the purpose of Plug and Play technology.
7) Explain the purpose of partitioning a drive.
8) Give an example of a complete path to a file, and explain the parts of the path.

References

  • Wiley, Computer Basics (2024)
  • ISACA (2021), Computing Fundamentals: Study Guide
  • O’Leary, D.A. et al (2021), Computing Essentials: making IT work for you (Introductory)
  • Crutcher, P.D. (2021), Essential Computer Science: A programmer’s guide to foundational concepts