Introduction to Computer Technology Module 4 Notes

Introduction to Computer Technology Topic 2 Module 4 Notes 4.1 Compare Operating Systems ● When you start your computer or device, system software starts running in the background, most include an operating system which is critical to the use ○ System Software: the software that runs a computer, including the operating system and utilities which control the behind-the-scenes operations of a computer or mobile device ○ Operating System (OS): a program that manages the complete operation of your computer or mobile device and lets you interact with it ■ Also called a platform ■ Most come pre-installed but it is possible to run one from another medium such as a flash drive ■ You can also run multiple OSs on some devices ■ Standard OS functions ● Starting and shutting down a device ● Managing programs ● Managing memory ● Coordinating tasks ● Configuring devices ● Establising an Internet connection ● Monitoring performance ● Providing file management ● Updating OS software ● Monitoring security ● Controlling network access ○ Graphical User Interface (GUI): a collective term for all the ways you interact with the device ■ Controls how you interact with menus, programs and apps, and visual images such as icons by touching, pointing, tapping, or clicking buttons and other objects to issue commands ○ Utilities: enable you to perform maintenance-type tasks related to managing the device ■ Tools that you use to manage files, search for content or programs, view images, install and uninstall programs and apps, compress and back up files, and maintain the device ● screen savers too ○ Softtware as a Service (SaaS): a software that is distributed online for a monthly subscription or an annual fee ○ Personal Computer (PC) Operating System: also known as a Desktop Operating System ■ Most are single-user operating systems because only one user interacts with the OS at a time ○ Closed Source Programs: keep all or some of the code hidden, enabling developers to control and profit from the program they create ■ Microsoft Windows and macOS ○ Open Source Programs: includes OS - has no restrictions from the copyright holder regarding modification and redistribution ■ Linux ○ Server Operating System: a multi-user OS because it controls a single, centralized server computer that supports many users on networked computers ○ Virtualization: the practice of sharing computing resources, such as servers or storage devices, among computers and devices on a network ■ Unless you’re a network administrator, you likely wont knowingly interact with a server OS ○ Mobile Operating System: smartphones, tablets and other mobile devices ■ Has features similar to desktop OS ■ Focused on the needs of a mobile user and the capabilities of the device ● Touchscreens, voice recognition, and Wi-Fi networks ○ Desktop: main workspace - contains icons for programs and files, toolbars, taskbars, menus etc. ○ Window: a rectangular-shaped work area that displays an app or collection of files, folders, and tools ○ Menu: a list of related items, including folders, apps, and commands ○ Dialog Boxes: windows with controls that let you tell the OS how you want to complete a command ○ File: a collection of information stored on your computer, such as a text document, spreadsheet, photo, or song ○ Data File: contains words, numbers, and pictures that you can manipulate ○ Executable File: contains the instructions your computer or device needs to run programs and apps ○ File Format: refers to the organization and layout of data in a file ○ File Extension: three or four letter sequences, preceded by a period, at the end of a file name that identifies the file as a particular type of document ■ .docx or .jpg ○ Folder: a named location on a storage medium that usually contains related documents ○ Library: a special folder that catalogs specific files and folders in a central location, regardless of where the items are actually stored on your device 4.2 Explain How an Operating System Works ● An OS takes cares of technical tasks of running the computer or device while you use it the essential software or app ■ Processes data, manages memory, controls hardware, and provides a user interface ○ The purpose of memory management is to optimize the use of a computer or device’s internal memory to allow the device to run more efficiently ○ Memory: consists of electronic components that store instructions waiting to be executed by the processor, data needed by those instructions, and the results of processing the data into information ■ Byte is the basic storage unit in memory ○ Volatile Memory: temporary, and loses its contents when the power is turned off ○ Nonvolatile Memory: permanent, its contents remain on the computer or device even when it is turned off ○ RAM (Random Access Memory): the storage location that temporarily stores open apps and document data while a device is on ○ Cache: frequently used instructions and data are stored here - temporary storage area desinged to help speed up processing time ○ Every program or app, including the OS, requires RAM ■ The more RAM a device has, the more efficiently it runs ○ Virtual Memory: the capabilit of an operating system to temporarily store data on a storage medium unil it can be “swapped” into RAM ■ The area of the hard drive used for virtual hard drive is called a Swap File ○ ROM (Read-Only Memory): nonvolatile memory - refers to memory chips that store permanent data and instructions ■ The data on most can’t be modified ○ Flash Memory: a type of nonvolatile memory that can be erased electronically and rewritten ■ Also store data and programs on many mobile and peripheral devices ■ microSD cards and such ○ Boot Process: before you can interact with the operating system the device goes through this process - triggers a series of steps and checks as the computer loads the operating system ■ The device receives power from the power supply or battery, and sends it to the circuitry ■ The processor begins to run the bootstrap program, which a special builtin startup program ■ The Bootstrap Program executes a series of tests to check the components, including the RAM, keyboard, and storage, and identifies connected devices and checks their settings ■ Once the tests are completed successfully, the computer or device loads the OS files into RAM, including the kernel ● The Kernal is the core of an OS, it manages memory, runs programs, and assigns resources ■ The device loads the system configuration information, prompts you for user verification if necessary, and loads all startup programs, such as antivirus programs or apps ○ Input: any data and instructions entered into the memory of a device ■ Interacting with a touchscreen or using a keyboard ■ Card readers and data collection devices ■ Game controllers and motion input devices ■ Microphones and webcams ■ Scanners ■ Touch pads or a mouse ○ Output: information processed into a useful form ■ Text, graphics, audio, video, or any combination of these ○ Buffer: an area of memory that stores data and information waiting to be sent to an input or output device ■ If a computer or device is slow in accepting or providing input or output the OS uses a buffer ○ Spooling: placing data into a buffer ■ When a document is sent to the buffer while it waits for the printer to be available ■ The OS frees up resources to perform other tasks while the data waits to be processed 4.3 Personalize an Operating System to Increase Productivity ● When you start using a computer or device, the OS and related software and hardware have default settings ○ Default Settings: standard settings that control how the screen is set up and how a document looks when you first start typing ○ Shortcuts: links to files and apps ○ Pointing Device: hardware device that lets you interact with your computer by controlling the movement of the pointer on your compute screen ■ Mouse, trackball, touchpad, pointing stick, on-screen touch pointer, tablet, or for touch-enabled devices, your hand or finger ○ Keyboard: main input device - contains not only characters such as letters, numbers, and punctuation, but also keys that can issue commands ○ Maximize and Minimize Buttons: enable you to expand a window so that it fills the entire screen or reduce a window so that it only appears as an icon on the taskbar ○ Close Button: closes the window, app, or document ○ Restore Down Button: reduces a window to its last non-maximized sized ○ Active Window: the window you are currently using, which appears in front of any other open windows ○ Program Window: displays a running program ○ Folder Window: displays the contents of a folder, drive, or device ○ Resources: the components required to perform work, such as the processor, RAM, storage space, and connected devices ○ Tile: shaded rectangle that represents an app or other resource ○ Icon: small picture that represetns a program, file, or hardware device ○ Button: a graphic that you click to execute commands you need to work with an app ○ Disk Cleanup Utility: finds and removes unnecessary files, such as temporary Internet files or files in teh Recycle Bin ○ Control Panel: collection of utility programs that determine how Windows appears and performs on your computer ○ Settings App: contains touch-friendly categories of the most commonly used Windows settings; more advanced settings are found in the Control Panel ○ Shortcut Menu: a list of frequently used commands that relate to an object, typically displayed by right-clicking; the commands on a shortcut menur are related to the item you right-clicked ○ Virtual Machine: enables a computer or device to run another OS in addition to the one installed ○ User Accounts: identify the resources a user can access when working with computer ○ Administrator Account: provides full access to the computer 4.4 Manage Files and Folders ● There are many ways to manage files and folders on your computer or device ○ File size is usually measured in Kilobytes (KB - thousands of bytes of data), Megabytes (MB - millions of bytes of data), or Gigabytes (GB - billions of bytes of data) ■ More data, larger the file and more storage it takes up ○ Cloud: a storage area located on a server that you access through the Internet or a network ○ Clipboard: a temporary Windows storage area that holds the selections you copy or cut so you can use them later