Technology in Action Chapter 5 System Software: The Operating System, Utility Programs, and File Management
Chapter Topics Operating System Fundamentals What the Operating System Does The Boot Process: Starting Your Computer The Windows Interface Organizing Your Computer: File Management Utility Programs
Pertinent Terms Software set of computer programs that enable hardware to perform different tasks Operating System A program that acts as an intermediary between a user of a computer and the computer hardware
Pertinent Terms: User Interface Users interact with the Operating System through the user interface A graphical user interface is like the standard windows interface with icons and pictures. A non-graphical user interface would be sole text based and you would see no pictures.
Layers of a Computer System The Operating system is the intermediary between the applications you use (e.g., MS Word and the Hardware (CPU)
Purpose of the OS Handles the management and allocation of computer resources 1. Manages the CPU 2. Memory Management 3. Device Management 4. Provides a UI
Event Each time user input occurs, or a command from an application, e.g., a keystroke, or play on a move, an event is generated. This event is set to the OS, indicating that a set of instructions should be executed to make the output from this event occur.
Event Execution The events are fed into the CPU The CPU stores the set of the events in the event table Then it executes the events in order of importance, and based on which came in first
Uniprogramming Single task Processor must wait for input/output operations to complete before proceeding E.g., While the computer is waiting for the user to enter the next letter, nothing happens
MultiTasking When one job needs to wait for I/O the CPU can process events from another job
Interrupt When an event is of high importance (e.g., a Skype call is coming in) it signals an interrupt Interrupts tell the OS that this event is in need of immediate attention and it s event gets put to the top of the priority, and will be executed quickly
Scheduling Jobs The OS uses multi-tasking and interrupt handling to schedule jobs When scheduling jobs, the OS strives for: Fairness Responsiveness to user Efficient utilization of processor time
Memory Management Makes sure the CPU has access to code and data it needs in main memory (RAM) The OS uses the RAM to store data and instructions that are needed by the CPU to perform tasks
Where is the OS? When a computer is turned on, portions of the OS are loaded into Main Memory. This portion is called the kernel and the memory it uses is kernel memory.
Memory Management The OS uses the RAM to store data and instructions that are needed by the CPU to perform tasks.
Running out of RAM If you are trying to run applications that require more RAM than your computer has available you can run out. In this situation the CPU borrows memory from the Hard Disk to work as Virtual Memory The Hard Disk takes longer to access data than the RAM so ideally you don t want to use Virtual Memory
Virtual Memory Terms Swap File - File on the hard drive storing copy of RAM contents Paging - Retrieve copies of RAM from the hard drive Thrashing - Repeatedly going back and forth between RAM and swap file
Running out of Virtual Memory The Hard Disk only allocates a certain amount of space for virtual memory. When this space runs out you experience Thrashing, and your computer becomes even more sluggish In this situation you can add more RAM to your computer, or buy a new computer.
OS Manages Hardware & Peripherals Device drivers - Programs that enable the OS to communicate with device Plug and Play - Driver included with OS, makes installation much easier
OS Provides a UI UI's enable you to interact with the computer, can be command line, graphical (GUI), etc...
Boot Process: Starting the The boot process loads the operating system into RAM Computer
Boot Process: Starting the Computer: Step 1: Activating BIOS CPU activates the basic input/output system (BIOS) BIOS Loads OS into RAM Stored on ROM
Boot Process: Starting the Computer: Step 2: Performing the Power-On Self-Test Power-on self-test (POST) Ensure the essential peripheral devices are attached and operational Compares results with CMOS (complementary metal-oxide semiconductor) CMOS contains info about memory, disk drives, and other essential hardware
Boot Process: Starting the Computer: Step 3: Loading the OS System files Loads OS into RAM Kernel is loaded Kernel: essential component of the OS Responsible for managing the processor and all components
Boot Process: Starting the Computer: Step 4: Checking Further Configurations and Customizations Checks registry for configuration of other system components Authentication Windows 8 Default setting: Microsoft account
Boot Process: Starting the Computer: Handling Errors in the Boot Process Uninstall recently installed software Use uninstall program or Control Panel Last Known Good Configuration Try refreshing your computer New in Windows 8 (see next slide)
The Boot Process: Starting the Computer: Handling Errors in the Boot Process Refresh your PC: New utility program in Windows 8 Attempts to diagnose and fix errors Back up PC prior to refreshing
The Boot Process: Starting the Computer: Handling Errors in the Boot Process During the boot process, BIOS can skip a device or improperly identify it Device won t respond Reboot Check for patches Technical assistance
Types of Operating Systems Single User Single Task: One user can perform one task at one time, e.g., palm pilot Single User Multitasking: One user can run multiple applications on their computer at one time, e.g., personal desktop and laptops
Types of Operating Systems Multi User - Networking systems, many users can access the computers resources at one time, e.g. Unix, Solaris, Linux, Windows Vista and up
RTOS (Real Time OS) Systems with a specific purpose and certain result Examples: Autos Airline reservations Robotic equipment
Understanding System Software: Operating Systems for Personal Computers Top three operating systems Windows Max OS X Linux
Understanding System Software: Operating Systems for Personal Computers Windows Most popular OS
Understanding System Software: Operating Systems for Personal Computers Mac OS Mavericks Mac OS X based on UNIX
Understanding System Software: Operating Systems for Personal Computers Linux Open source OS Personal computer and network OS
Understanding System Software: Operating Systems for Personal Computers More than one OS on one computer Boot Camp utility in OS X Parallels or VMware Fusion for Windows Partition hard drive in Windows VirtualBox by Oracle
Utility Programs Utility Programs are: Part of the OS Tools that helps manage the computer Small programs that perform special functions Examples? Backup/Restore Security Diagnostic Data Compression Display Utilities Accessibility Utilities
Utility Programs Backup - Creates a copy of the data to another storage device or location Task Scheduler - Runs selected utilities automatically
Utility Programs: System Restore and Backup Utilities System restore point Made every week Before installing software Custom restore point
Utilities Security User sign on and password support Auto logoff Firewall Encryption routines Windows allows other apps to interface with it to provide security
Utility Programs Disk Cleanup Removes unnecessary files Choose files to be deleted: Downloaded Program Files Temporary Internet Files Offline Web Pages Recycle Bin
Utilities Disk defragmenter - Regroups related pieces of files Error checker - Checks for lost files and file fragments Task Manager - Checks on non responsive programs
Utilities File Compression Reduce the size of a file Take out redundancies Makes it faster/easier to send files over internet Generally, repeated patterns are replaced with a shorter placeholder The rain in Spain falls mainly on the plain.
Utilities Display utilities change the appearance of: Desktop Background Screensaver Window Colors
Utility Programs: Accessibility Utilities Ease of Access Center
Utility Programs: The Programs and Features Utility Installing a new program Installation wizard
Organizing Your Computer: File Management Additional function of the operating system Organizational structure Hierarchical directory structure Folders Libraries Drives Root directory
Organizing Your Computer: File Management: Organizing Your Files File Folder Library
File Extensions Operating systems like MS Windows rely heavily on extensions
Organizing Your Computer: File Management: Naming Files File Save Location Determine location of a file by its file path File path
Organizing Your Computer: File Management: Working with Files File-management actions Open Copy Move Rename Delete
Organizing Your Computer: File Management: Working with Files Recovering deleted files File History utility File retrieval programs FarStone s RestoreIT Norton Ghost
Assignment 01 Found in Blackboard and on class site. Due in two weeks Overview: Report on the hardware and software of your own computer. Configure a new computer that meets your computing needs.
Next Time Networking Read Chapters 3 & 7
Quiz Flip over your notes Cover open books Everyone use the scantron Make sure you it has your name and id 54