1 Intro to Info Tech Systems S/W Copyright 2003 by Janson Industries This presentation can be viewed on line at:

Copyright 2014 by Janson Industries 2 Objectives n Explain 2 types u Operating Systems F The general purpose of F Specific tasks of u Utility Programs F Types of

Copyright 2014 by Janson Industries 3 Operating System n Set of programs that: u Enable h/w to function u Provide a user interface u Manage system resources F Configure devices F Schedule jobs F Monitor: Performance Memory Applications u Provide security

Copyright 2014 by Janson Industries 4 Operating System n Set of programs that: u Enable users to run applications u Provide common functions for applications F Printing F Saving and retrieving files This is how OS came about u Establish Internet connections

Copyright 2014 by Janson Industries 5 Operating Systems n PCs use Windows, Linux, or OSX (Macs) u Some computers can run multiple n Midrange and mainframes use different OS n OS also called a platform: n Applications written for specific platforms u Must buy correct application for your platform

Copyright 2014 by Janson Industries 6 OS Functions n Booting: starting the computer u Cold boot: powering on the computer u Warm boot: restarting n When installing new applications, often must reboot (warm boot) n OS programs stored on hard drive n When booting: u Kernel loaded into main memory F Kernel comprised of those programs that provide basic OS functions F Remains in MM

Copyright 2014 by Janson Industries 7 OS Interfaces n Interface is the way users can enter data and instructions and how information is displayed n Two types: u Command Line Interface (CLI) u Graphical User Interface (GUI) n Command line requires commands and syntax n GUI is point and click

Copyright 2014 by Janson Industries 8 GUI Clicked on icons Command line Entered command and pressed Enter

Copyright 2014 by Janson Industries 9 OS Categories n Identified by how many tasks and users it can support simultaneously n Single user/single task u Smaller devices only allow one user to run one application at a time n Single user/multi-tasking u Can run many apps at the same time u Only one app is active

Copyright 2014 by Janson Industries 10 OS Categories n Multi-user u Many users can run many apps at the same time F Larger computers F Networks n Multi-processor u Supports many CPUs and many active jobs F Many apps can be running simultaneously

Copyright 2014 by Janson Industries 11 OS n Manages MM u OS assigns memory to applications u When apps done, releases memory n Sometimes apps too big for RAM n Solution: Virtual Memory u App broken up into pages (pieces) u Pages loaded into MM as needed u Removed when not needed

Copyright 2014 by Janson Industries 12 OS n Also sets up and manages buffers u Memory that acts as a waiting area n Classic example: print buffer u Printer slow compared to CPU u Instead of CPU waiting for printer to accept next print job u Output sent to buffer u When printer ready u Output retrieved from buffer and sent to printer n This process is called SPOOLing u Simultaneous Peripheral Operations On Line

Copyright 2014 by Janson Industries 13

Copyright 2014 by Janson Industries 14 n Set up date/time to run an app Where to storeWhat to store When to store

Copyright 2014 by Janson Industries 15 Scheduling Jobs n In multi-user environment OS will allow priorities to be assigned u By user F CEO has highest priority u By type of job F Print job higher than browsing web u Availability of resources F External storage busy

Copyright 2014 by Janson Industries 16 Configuring Devices n Each device has its own commands n OS contains "drivers" (programs) to communicate with the most common devices n Drivers loaded into MM when computer started n If OS doesn't have driver, you may have to install the driver u Usually comes with device or easily downloaded from the Web

Copyright 2014 by Janson Industries 17 Monitor Performance n CPU utilization

Copyright 2014 by Janson Industries 18 Can see multiple resources at a time

Copyright 2014 by Janson Industries 19 Monitor Performance n Disk space used/available

Copyright 2014 by Janson Industries 20 Monitor Performance n App/process monitoring

Copyright 2014 by Janson Industries 21 Monitor Performance n Disk fragmentation n Analyses first, then, if needed, defrag

Copyright 2014 by Janson Industries 22 File Management n Organize in folders n Copy n Delete n Search Search particularly helpful when you forgot where you saved it or what you named it

Copyright 2014 by Janson Industries 23 File Management n Disk scanner u Looks for unused/temp files u Looks for uncompressed files u Lets you easily delete and compress them

Copyright 2014 by Janson Industries 24 n Uninstaller u Easily remove an app

Copyright 2014 by Janson Industries 25 Security n Create Userids and Passwords u Force users to log on to the computer u Enforce at file and application level n Keeps track of incorrect log on attempts u May disable Userid after a certain number of incorrect attempts n Keeps track of unauthorized attempts to access files and apps

Copyright 2014 by Janson Industries 26 Security n Most provide some firewall u Protects computer from unauthorized access F I.e. you download a web page that contains a program that looks through hard drive and for Credit Card numbers SSN Bank Statements n Some anti-virus protection n Usually need utility programs for better/most up to date security

Copyright 2014 by Janson Industries 27 Lots of OS n Handheld – Palm, Symbian (Nokia), Blackberry OS, Android, iPhone, Windows Phone 7 n PC – Windows, OS X, Linux n Midrange – Solaris, IBM i, Linux n Mainframe – MVS, VM, Unix, Linux n Most are proprietary, Linux and Android are open source u Said another way: most you must pay for, open source is free

Copyright 2014 by Janson Industries 28 Open Source vs. Closed Source n Open source price is better - pro n But if everyone can see source code u Greater security risk - con u More eyes to catch errors - pro u More programmers can work on to improve - pro n But if not paid for it, what's the incentive to build/maintain open source s/w? - con

Copyright 2014 by Janson Industries 29 Utility Programs n S/W that enables the computer to work better u Example: F Potential 75% decrease in ink used F Would you pay $32 for that? n MS continually crams more into OS that was handled by stand alone utils n However, stand alones usually do a better job than those utilities included in Windows u Can buy u Often a free version available online

Copyright 2014 by Janson Industries 30 Utility Programs Types n Antivirus u Virus: s/w that will harm or impede your computers applications and data F Some harmless: Yankee Doodle F Some not: Michaelangelo n Two types: u Worms – replicate themselves u Trojan horse – hidden in other s/w, , etc.

Copyright 2014 by Janson Industries 31 Utility Programs Types n Spyware and Spyware removers u You may want to install u Websites will install without permission F Spyware removers usually also remove adware n Internet filters u Antispam: usually included in app (MS Outlook) or by provider u Web filter: usually included in browser (MS IE, Firefox, Chrome, etc.) u Pop up blocker: usually included in browser

Copyright 2014 by Janson Industries 32 Utility Programs Types n File compression: zip and unzip files to save space on drives u OS will often do automatically u PKZIP, WinZip n File conversion u WAV to MP3, Word to PDF, Access to Excel n Media Players u Why not just use Media Player? u Can it access your iPod? u Need iTunes

Copyright 2014 by Janson Industries 33 Points to Remember n Operating Systems enable the computer hardware to work n Provides a GUI and commands to perform system functions n Enable the h/w and applications to function For classroom based classes: Bring your thumb drive to the next class