Author name: contact@devinevisiontech.com

OPTOMETRY · SEMESTER 1 Planned Preventive Maintenance Computer Applications START READING NOTES Contents of This Topic What is PPM? Planned Preventive Maintenance TYPES OF PPM Objectives of Planned Preventive Maintenance (PPM) 4. Ensure Safety & Compliance significances of PPM 2. Improved safety 5. Better reliability BRAIN STORM??? PPM procedures to protect the computer from environmental damage 2. Protection from Extreme Temperatures 3. Protection from Moisture General Preventive Maintenance Steps PPM Procedures to Protect Computers from Power Surges 2. Install Surge Protectors 3. Implement Proper Power Management 4. Ensure Proper Electrical Grounding 5. Schedule Routine Inspections & Maintenance PPM Procedures to Protect Computers from Malware, Adware, and Viruses 2. Install and Maintain Security Software 4. Safe Internet and Email Practices 6. Restrict External Device Use Possible Questions Introduction to Planned Preventive Maintenance (PPM) What is PPM? Planned preventative maintenance is a form of scheduled or planned maintenance that is carried out on a piece of equipment or machinery on a regular basis. Planned preventative maintenance is used to reduce machine downtime, keep the performance of the machine level high and prevent issues from occurring. PPMs are incorporated into machine service plans to prevent high levels of reactive maintenance, instead, a good PPM program can turn reactive work into a predictive and proactive strategy. OR Planned Preventative Maintenance (PPM) is a proactive maintenance strategy where equipment, systems, and assets are serviced at scheduled intervals to prevent unexpected failures. The goal is to keep everything in optimal working condition, minimize downtime, and extend the lifespan of critical assets. This method is widely used across industries to ensure efficiency and reliability. Planned Preventive Maintenance Planned Preventive Maintenance (PPM) is a proactive approach to maintenance that involves regularly scheduled inspections, tests, and repairs to equipment, facilities, and systems in order to prevent breakdowns and minimize the risk of equipment failure. The goal of PPM is to extend the lifespan of equipment and facilities, improve their performance and reliability, and reduce the risk of downtime and unplanned repairs. TYPES OF PPM Planned Preventive Maintenance (PPM) is categorized into different types based on scheduling, execution, and purpose. Below are the main types: 1. Time-Based Maintenance (TBM) : Maintenance performed at scheduled intervals (daily, weekly, monthly, or annually) regardless of equipment condition. ✔ Example: Changing air filters in computers every three months. ✔ Use Case: Suitable for components with predictable wear and tear. 2. Condition-Based Maintenance (CBM) : Maintenance is performed when equipment shows signs of wear or potential failure. ✔ Example: Cleaning dust buildup from a computer’s cooling fan when temperatures start rising. ✔ Use Case: Used for critical systems where early warning signs indicate maintenance needs. Planned Preventive Maintenance 3. Predictive Maintenance (PdM) : Uses data and monitoring tools (e.g., sensors, AI, machine learning) to predict failures before they happen. ✔ Example: Monitoring server temperature and scheduling fan replacements before overheating occurs. ✔ Use Case: Applied in high-tech environments where system downtime must be minimized. 4. Risk-Based Maintenance (RBM) : Prioritizes maintenance based on risk assessment, focusing on high-risk equipment first. ✔ Example: Regularly inspecting UPS systems in hospitals to prevent sudden power failures. ✔ Use Case: Useful in healthcare, aviation, and industrial sectors where failures can have severe consequences. Planned Preventive Maintenance 5. Corrective Preventive Maintenance: A combination of preventive and corrective maintenance, addressing minor issues before they escalate. ✔ Example: Replacing a hard drive that shows bad sectors before it completely fails. ✔ Use Case: Ideal for IT systems and industrial machinery 6. Prescriptive Maintenance (RxM) : Uses advanced analytics and AI to suggest the best maintenance actions. ✔ Example: An AI-powered system analyzing historical data and recommending when to replace server components. ✔ Use Case: Applied in smart hospitals, IoT-driven industries, and cloud computing environments. NOTE: By implementing the right type of PPM, organizations can enhance efficiency, reduce costs, and extend equipment lifespan Objectives of Planned Preventive Maintenance (PPM) Planned Preventive Maintenance (PPM) is designed to ensure the efficiency, reliability, and longevity of equipment. The key objectives include: 1. Minimize Equipment Failure & Downtime ✔ Prevents unexpected breakdowns by addressing potential issues early. ✔ Ensures continuous operation, reducing disruptions in workplaces like hospitals and data centers. 2. Extend Equipment Lifespan ✔ Reduces wear and tear, keeping systems in optimal condition. ✔ Prevents premature replacement of expensive components. 3. Reduce Maintenance & Operating Costs ✔ Avoids costly emergency repairs by addressing small issues before they escalate. ✔ Improves energy efficiency, lowering electricity and operational costs. 4. Ensure Safety & Compliance ✔ Reduces risks of accidents caused by equipment failure. ✔ Helps organizations comply with industry regulations and safety standards (e.g., ISO, OSHA). 5. Improve Performance & Reliability ✔ Keeps equipment operating at peak efficiency. ✔ Reduces system lag, overheating, and software malfunctions. 6. Optimize Resource Utilization ✔ Ensures spare parts and labor are used efficiently. ✔ Reduces unnecessary downtime, maximizing productivity. 7. Protect Data & IT Systems ✔ Prevents hardware failures that can lead to data loss. ✔ Reduces security risks by keeping software and firmware updated. significances of PPM Planned preventative maintenance (PPM) offers several advantages, including: 1. Increased equipment lifespan Regular pre maintenance can help extend the lifespan of equipment and reduce the likelihood of breakdowns and failures. 2. Improved safety By identifying and fixing potential hazards before they cause an issue, PPM can help improve safety for employees and equipment. 3. Increased efficiency Well-maintained equipment runs more efficiently and effectively, reducing the need for repairs and downtime and increasing productivity. 4. Cost savings Regular maintenance can help identify small problems before they become big and expensive issues, reducing the need for costly repairs and replacements 5. Better reliability PPM helps to ensure that equipment is always in good working order, reducing the risk of unexpected breakdowns and helping to maintain a reliable production schedule. 6. Improved facilities appearance Regular maintenance can help keep facilities looking their best, improving the overall appearance and reputation of the business. 7. Better decision-making By keeping track of equipment performance and maintenance activities, PPM can

OPTOMETRY · SEMESTER 1 Internet and Email Skills Computer Applications START READING NOTES Contents of This Topic Session 04: INTERNET What Is the Internet? Other types of network are: Types of network cont.…… Internet connects millions of computers, webpages, websites, and servers together. 1.Hub Difference between Internet and Intranet How do I connect to the Internet? Internet Service Provider Modem What is Web or WWW? What is Browser? URL (UNIFORM RESOURCES LOCATOR) Protocol Domain name (top level domain) DOMAIN NAME Domain name of a host computer includes Example Common Abbreviations in URLs Internet Communications Types of Internet service Advantages of using internet Internet and Email Skills Disadvantages of using internet Search information using internet There are many different search engines you can use, but some of the most popular include Google, Yahoo!, and Bing. How to search information on the internet(Google) Homework Download files from internet When users want to keep the data on their device, they download the data to it. Creating an Email account and manage messages Email messages are usually encoded in American Standard Code for Information Interchange (ASCII) format. The main components of an email message Typically, an email header contains the following information: Recipient email address. This is the email address of the recipient or where the message was sent. ADVANTAGES OF E-MAILS DISADVANTAGES OF E-MAIL Disadvantages of email Creating an Email account(Email address) Steps to create Gmail account Steps to send email in Gmail Steps to send email attachment in Gmail HOMEWORK MODULE: COMPUTER APPLICATIONS Session 04: Apply internet and email skills in accessing medical records Learning Objectives Describe terminologies related to internet Explain the advantages and disadvantages of using internet Search information using internet Download different files from the websites Create an email account and manage messages Send file through Email INTERNET Can you remember a time when you could not tweet, post, email, blog, snap, streaming or like someone online? Many people today have grown up being able to do all of these things. But there was a time when none of this was possible. What makes this possible today is what we call the Internet. What Is the Internet? The Internet is a global wide area network that connects computer systems across the world. What is a network? Refers to interconnected computing devices that can exchange data and share resources with each other. The Internet is the most basic example of a Wide area network (WAN), connecting all computers together around the world. Other types of network are: Local area network (LAN) – Network that covers small geographical area like office, building or small college. Metropolitan area network (MAN) – Network that covers large area like City , multiple cities or towns Virtual Private Network (VPN) Creates a secure, encrypted connection between devices, allow them to communicate privately over a public network like the internet. Types of network cont.…… Wireless Local Area Network (WLAN) Is a LAN that uses wireless technology (like Wi-Fi) to connect devices. Storage Area Network (SAN) Is a high speed network that connects storage devices (like hard drives) to servers, enabling efficient data transfer and storage. Internet connects millions of computers, webpages, websites, and servers together. Using the internet we can send emails, photos, videos, messages to our loved ones. If your device is connected to the Internet then only you will be able to access all the applications, websites, social media apps, and many more services. Internet nowadays is considered as the fastest medium for sending and receiving information. 1.Hub 2.Switch 3.Router 4.Bridge 5.Gateway 6.Modem 7. Repeater 8.Access Point 9.Server 10.Computer Here are the common network devices: Difference between Internet and Intranet Generally, most people are confused between the internet and the intranet. While there are exist lots of differences to differentiate them. Intranet is the type of internet that is used privately. It is a private network therefore anyone can’t access the intranet. On the intranet, there is a limited number of users and it provides a piece of limited information to its users. How do I connect to the Internet? Once you've set up your computer, you may want to purchase Internet access so you can send and receive email, browse the Web, stream videos, and more. There are three ingredients needed to access the Internet from a laptop or desktop computer: an ISP (Internet service provider) a modem and a Web browser Internet Service Provider The term “internet service provider (ISP)” refers to a company that provides access to the internet to both personal and business customers ISPs make it possible for their customers to surf the web, shop online, conduct business, and connect with family and friends—all for a fee. Examples of ISP in Tanzania are TTCL, Vodacom, Airtel e.t.c Modem Is a computer hardware device that converts data from a digital format into a format suitable for an analog transmission medium such as telephone or radio. What is Web or WWW? The World Wide Web (WWW), commonly known as the Web, is an information system enabling documents and other web resources to be accessed over the Internet. The Web uses HTTP protocol to transmit data and share information. Browsers are used to access Web documents, or Web pages and other web resources such as pictures, videos and audio What is Browser? Is a software application used to access information on the World Wide Web( WWW) Is application software for accessing websites. Browsers are used on a range of devices, including desktops, laptops, tablets, and smartphones. The most used browsers are Google chrome, Microsoft Edge, Mozilla Firefox, Opera mini, Safari, Brave, Netscape Navigator etc. The purpose of a web browser is to fetch content from the World Wide Web or from local storage and display it on a user's device. This process begins when the user inputs a Uniform Resource Locator (URL), such as https://www.mccohas.ac.tz, into the browser. URL (UNIFORM RESOURCES LOCATOR) Is the pathname to display resources available on internet List the parts of URL Protocol name Host part Domain

OPTOMETRY · SEMESTER 1 Microsoft Excel Computer Applications START READING NOTES Contents of This Topic Related tasks Advantages of MS EXCEL Disadvantages of MS EXCEL MS General Features Outlines Microsoft Excel Introduction MS Excel General overview There are various ways to navigate through a worksheet: Selecting Cells, Rows, and Columns Editing & Formatting Worksheets Formatting Numbers Inserting Rows and Columns Deleting Rows and Columns Changing Column Widths Changing Row Heights Hiding Rows and Columns Unhiding Rows and Columns Selecting Worksheets Navigating Between Worksheets Renaming Worksheets Inserting Worksheets Deleting Worksheets Moving Worksheets Copying Worksheets MS Excel Views -The Normal View MS Excel Views – Page Layout View MS Excel Views – Page Break Preview View MS Excel Views – Custom Views Allows you to save a set of display and print settings as a custom view, and then apply it. Freezing and Unfreezing Panes Using Templates MICROSOFT EXCEL Related tasks Meaning of MS excel Advantages and Disadvantages of MS EXCEL MS General Features General overview of MS Excel Advantages and Disadvantages of MS EXCEL Advantages of MS EXCEL i. The Best Way to Store Data ii. It perform calculations iii. It has all the tools for data analysis iv. Easy to make data visualizations with charts v. You can print reports easily vi. It has So many free templates to use vii. You can save the document in different formats viii. It Store data with millions of rows Disadvantages of MS EXCEL Difficult to Learn ii. Difficult Formulas application iii. No Quick Autofill features iv. Calculation Errors MS General Features title bar quick access tool bar Menu bar standard toolbar Formatting toolbar active cell columns header rows header document view worksheet MS General Features MS General Features Outlines Introduction MS Excel General overview Moving Around Worksheets Selecting Cells, Rows, and Columns Editing & Formatting Worksheets Formatting Numbers Inserting Rows and Columns Deleting Rows and Columns Changing Row Heights Changing Column Widths Hiding and Unhiding Rows and Columns Selecting Worksheets Navigating Between Worksheets Renaming Worksheets Inserting Worksheets Deleting Worksheets Moving Worksheets Copying Worksheets MS Excel Views The Normal View Page Layout View Page Break Preview View Custom Views Full Screen View Freezing Panes Using Templates Microsoft Excel A spreadsheet: is a table of values arranged in rows and columns; the intersection of a Row & Column is called a Cell. Each cell can have a predefined relationship to the other cells. If you change the value of one cell, the values in the other cells may also be changed according to their relationships with that cell. Introduction Introduction Excel is the MS-Office Application program used for creating spreadsheets. You can use Excel to enter all sorts of data and perform financial, mathematical, or statistical calculations. Excel operates like other MS Office programs and has many of the same functions and shortcuts as MS Word & MS PowerPoint. Excel is more widespread, quick, and easy. MS Excel General overview An Excel file or a workbook: is composed of a number of worksheets (could be more than 200) MS Excel General overview An Excel file or a workbook: is composed of a number of worksheets (could be more than 200) Sheet tabs: each tab represents a different worksheet in the workbook. MS Excel General overview An Excel file or a workbook: is composed of a number of worksheets (could be more than 200) Sheet tabs: each tab represents a different worksheet in the workbook. Active Worksheet MS Excel General overview An Excel file or a workbook: is composed of a number of worksheets (could be more than 200) Sheet tabs: each tab represents a different worksheet in the workbook. Active Worksheet Row headers MS Excel General overview An Excel file or a workbook: is composed of a number of worksheets (could be more than 200) Sheet tabs: each tab represents a different worksheet in the workbook. Active Worksheet Row headers Column headers MS Excel General overview An Excel file or a workbook: is composed of a number of worksheets (could be more than 200) Sheet tabs: each tab represents a different worksheet in the workbook. The Active Cell: is the selected cell, and has a thicker black border around it. Active Worksheet Row headers Column headers MS Excel General overview The Name Box: displays the active cell address or the name of the selected cell, range, or object. An Excel file or a workbook: is composed of a number of worksheets (could be more than 200) Sheet tabs: each tab represents a different worksheet in the workbook. Active Worksheet The Active Cell: is the selected cell, and has a thicker black border around it. Row headers Column headers MS Excel General overview The Name Box: displays the active cell address or the name of the selected cell, range, or object. Formula Bar: displays the data or formula stored in the active cell. An Excel file or a workbook: is composed of a number of worksheets (could be more than 200) Sheet tabs: each tab represents a different worksheet in the workbook. Active Worksheet The Active Cell: is the selected cell, and has a thicker black border around it. Row headers Column headers There are various ways to navigate through a worksheet: Use the mouse and the scroll bars to scroll through the worksheet in any direction. Use the navigational keys on the keyboard: Down arrow or Enter: for moving the active cell one cell down. Up arrow or Shift+ Enter: for moving the active cell one cell up. Right arrow or Tab: for moving the active cell one cell to the right. Left arrow or Shift+Tab: for moving the active cell one cell to the left. Page Down for moving the active cell down one page. Page Up: for moving the active cell up one page. Alt+Page Down: for moving the active cell right one page. Alt+Page Up: for moving the active cell left one page. Ctrl+Home: for moving the active cell to cell A1. Ctrl+End: for moving the active cell to the

OPTOMETRY · SEMESTER 1 PowerPoint Presentation Skills Computer Applications START READING NOTES Contents of This Topic Apply presentation skills in information dissemination Define PowerPoint PowerPoint versions Launch/start PowerPoint in Windows 7 Launch/start PowerPoint in Windows 8, 10, 11 A. Office Button F. Slide Area K. Outline tab Create PowerPoint presentation I. Create a PowerPoint Presentation from blank slides II. Create a PowerPoint Presentation using a template III. Create a PowerPoint Presentation from word outline PowerPoint presentation views Home work Adding new slide to a presentation Delete slide Save your presentation Format text of a PowerPoint presentation Add clipart and picture in presentation Add SmartArt Add charts, diagrams and tables in presentation Add charts, diagrams and tables You can change table styles and also insert and delete rows and columns Add AutoShape, WordArt and Hyperlinks Add WordArt Add Hyperlinks and action button If you use text for the hyperlink, the Text to display field will appear active in the dialog box. PowerPoint Presentation Skills Insert the shape onto the slide. The Actions Setting dialog box will appear. Add footer, slide number and date Add transition to a presentation(2013-2021) Click the Transitions tab. You can modify transition by changing the following properties Add transition to a presentation(2007) Add animation to a presentation Add animation to a presentation (2007) Add animation to a presentation (2013-2021) Select the Animation tab and options in the ribbon appear. Print a PowerPoint presentation (2007) Decide what you want to print: slides, handouts, notes pages, or an outline. Print a PowerPoint presentation (2013-2021) Choose which slides you want to print: Under Settings, click the first rectangle's down arrow and choose an option: Power Point Presentation Apply presentation skills in information dissemination Learning Objectives Define PowerPoint program Launch/start PowerPoint program Create PowerPoint presentation Format text of a PowerPoint presentation Add clip art and pictures in PowerPoint presentation Add charts, diagrams and tables in presentation Add AutoShapes, WordArt and hyperlinks in presentation Create animate slides Add transitions to a presentation Print a PowerPoint presentation Define PowerPoint PowerPoint is a software package designed to create electronic presentations consisting of a series of separate pages or slides. Sometimes abbreviated as PP or PPT This program developed by Microsoft Corporation It is a standard component of the company's Microsoft Office suite software, and is bundled together with Word, Excel and other Office productivity tools. PowerPoint versions PowerPoint 2003 (version 11) (Office 2003) PowerPoint 2007 (version 12) (Office 2007) PowerPoint 2010 (version 14) (Office 2010) PowerPoint 2013 (version 15) (Office 2013) PowerPoint 2016 (version 16) (Office 2016) PowerPoint 2019 (version 16) (Office 2019) PowerPoint 2021 (version 16) (Office 2021) Launch/start PowerPoint in Windows 7 You may use one of the following methods: Click the Start button on the Windows taskbar, then select All Programs, Microsoft Office, PowerPoint. If PowerPoint has recently been used on the computer or has been pinned to the Start Menu, it will appear on the first Start menu list. If so, click the shortcut to start the program. If PowerPoint has been pinned to the taskbar, the PowerPoint icon will be displayed after the Start button on the taskbar. Click the PowerPoint icon to start the program. If available, you may also double-click the PowerPoint shortcut on the Windows Desktop. Launch/start PowerPoint in Windows 8, 10, 11 From the Start screen, click or tap the PowerPoint tile. You will then switch to the Desktop, where PowerPoint runs. From the All Apps screen, click or tap the PowerPoint icon. You will then switch to the Desktop, where PowerPoint runs. On the Desktop, click the PowerPoint Quick Launch icon in the taskbar. 6 PowerPoint window elements (2007) A. Office Button Used to open a new presentation, save the presentation, and access PowerPoint options. B. Quick Access Toolbar Also known as the QAT, this is a customizable toolbar placed by default next to the Office Button, you can add icons for your often used commands to this toolbar C. Title bar This shows the title/name of your presentation and program that you are using D. Close button Used to close the current presentation E. Ribbon The Ribbon has tabs which in turn contain groups of buttons for various options, some groups also contain galleries (for example galleries for Themes and Theme Colors) F. Slide Area Used to display the active slide G. Notes pane Is where you input speaker notes for the current slide. None of this content is visible on the actual slide while presenting, although it is visible in both Notes Page view and Presenter view. H. Zoom button This shows the title/name of your presentation I. View button Used to view presentation in different views (normal view, slide sorter view and slideshow) J. Status bar Shows messages and information about the view, such as the slide number and the current theme template used. K. Outline tab Used to view presentation text and edit it L. Slide tab Used in normal view to navigate from one slide to another PowerPoint window (2013 – 2021) Create PowerPoint presentation To begin working with PowerPoint, you will need either to open an existing presentation or create a new one. They are 3 ways of creating PowerPoint presentations Create a PowerPoint Presentation Using a Template Create a PowerPoint Presentation from Blank Slides Create a PowerPoint Presentation from a Word Outline I. Create a PowerPoint Presentation from blank slides Step 1.From the File menu, select New. (In Microsoft 2007, select the Microsoft Office button and click New.) Step 2. Double Click Blank Presentation or (Select blank presentation and click create button) II. Create a PowerPoint Presentation using a template Step 1. From the File menu, select New. (In Microsoft 2007, select the Microsoft Office button and click New.) Step 2. Double Click one of the templates or (Select template you want and click create button III. Create a PowerPoint Presentation from word outline In Word 2007-2022, you will need to add the “Slide from outline" option to the "Quick Access Toolbar." Click the arrow at

OPTOMETRY · SEMESTER 1 Computer Memory and Operating Systems Computer Applications START READING NOTES Contents of This Topic Session 3 Session Objectives Session Objectives [Contd…] Archie, please return My $1000 Computer Memory Visualisation of Computer Memory Dictionary of Bits and Bytes Dictionary of Bits and Bytes contd… Dictionary of Bits and Bytes contd… Introduction To Operating System Introduction To Operating System contd… Definition of OS Functions of Operating System Functions of Operating System [Contd…] Therefore EDP CYCLE Components of the CPU CPU Registers ALU Control Unit (CU) Classification Of Operating Systems Classification Of Operating Systems [Contd…] OTHER CLASSIFICATION OF OS By Functionality Modern ExamplesOF OS Graphical User Interface Systems Components Of GUI System Components Of GUI System [Contd…] Components Of GUI System [Contd…] Session Summary Session 3 Memory and Operating System Session Objectives Explain the concept of computer memory Describe the logical structure of computer memory List the different units for measurement of computer memory Explain the concept of operating system Describe EDP cycle in detail Session Objectives [Contd…] Describe the CPU Architecture. Describe about the CPU registers Name the categories of operating system Explain the features of GUI systems List the features of an OS Archie, please return My $1000 Which money Tom, I can’t remember!!! Need for Memory Computer Memory The capacity of the computer to store data at an instant and its ability to retrieve the same data at another point of time is termed as the computer memory. Memory is used to store both data and information Computer’s memory can be visualized as a contiguous block of rectangular holes. Visualisation of Computer Memory Look at the Shelf Tom, Cell Block of Memory Contents(Data or Information) Dictionary of Bits and Bytes Data given by the user is either decimal numbers or alphabets. So, a step of conversion is necessary before the inputs get accepted by the computer. Hey!!! I can understand only 0s and 1s Dictionary of Bits and Bytes contd… 2 Numbers and alphabets get converted into binary numbers 0 1 0 Bit(Binary Digit) Conversion program Dictionary of Bits and Bytes contd… 8 Bits= 1 Byte 1 TB 1024MB=1GB 1024 KB=1MB 1024 Bytes= 1KB Tera Byte Introduction To Operating System Office Environment I want the Year End financial report !! Yes Sir, Introduction To Operating System contd… User Take these numbers and give me their sum. OS Ok Sir, It will be done Computer Environment Definition of OS OS is a system software which acts as an interface between the user and the computer hardware. Functions of Operating System Booting loads the user program into the computer memory The data required by the program is also loaded into the memory. Gives instruction to the computer to display the result on the monitor Functions of Operating System [Contd…] Provides the means for the proper use of the resources like input,output and storage devices. Thus it acts as a manager of various computer resources. Functions of Operating System [Contd…] The operating system software controls the computer hardware. It co-ordinates the flow of data from the storage unit to the processor and vice versa. Therefore An OS is responsible for forwarding the inputs to the processor, get the computation done, and display the result This process is popularly also known as the EDP cycle. EDP CYCLE INPUT DEVICES CPU BUFFER OUTPUT DEVICES PRIMARY MEMORY Components of the CPU CPU Registers CU ALU CPU Registers This unit is for storing any data that comes into the CPU while processing. ALU The Arithmetic and Logic Unit or the ALU takes care of all the mathematical and logical Operations to be done during calculations. Control Unit (CU) This unit controls the whole process of data transfer from one place to the other while computations are going on Classification Of Operating Systems Operating Systems can be categorized into two types. Single User Operating System Example: MS DOS User Processor Classification Of Operating Systems [Contd…] Multi – User Operating System A computer system, when acts as an interface for more than one user, it becomes a multi user environment system Example: Windows -NT Classification Of Operating Systems [Contd…] 4 OS is carrying User1’s Work to the processor I have some work for you Mr. OS The OS puts User2’s work in queue I have some work for you Mr. OS 1 USER1 USER2 3 5 User’s 1 job can be collected back and hence User2’s work is taken up 6 Processor OS 2 OTHER CLASSIFICATION OF OS By Device & Use Case Desktop/Laptop OS: Windows, macOS, Linux (Ubuntu, Fedora), ChromeOS. Mobile OS: Android, iOS (for iPhones/iPads). Server OS: Linux distributions (Ubuntu Server, Red Hat), Windows Server. Embedded OS: For specialized devices like smart TVs, cars, ATMs (often proprietary or stripped-down Linux/RTOS). Real-Time OS (RTOS): Critical for precise timing, used in medical devices, robotics, automotive systems (e.g., VxWorks, QNX). By Functionality Multi-Tasking: Runs multiple applications at once (Windows, macOS, Linux). Multi-User: Allows multiple users to access the system simultaneously (Linux, Windows Server). Time-Sharing: Divides CPU time among users for quick response (modern multitasking OS). Distributed: Manages multiple computers as one system over a network. Network OS (NOS): Manages network resources and communication. Batch OS: Processes jobs in batches without direct user interaction (older systems). Modern ExamplesOF OS Windows: Most popular on desktops, known for broad software compatibility. macOS: Apple's OS for Macs, known for user experience and ecosystem integration. Linux: Open-source, dominant in servers and supercomputers, many variations (distributions). Android: Open-source, highly customizable, powers most smartphones. iOS: Apple's mobile OS, known for security and simplicity on iPhones/iPads. Graphical User Interface Systems OS which use pictures on its interface to abstract functionalities are GUI(Graphical user Interface) OS Hence the user can just point and select appropriate pictures to invoke the required functionality of the OS Example : Windows OS : Win ’95 and Win NT. Components Of GUI System Desktop This is an area on the screen, which displays the various components of a GUI. It is always the starting screen to the OS environment.

OPTOMETRY · SEMESTER 1 Computer System Components Computer Applications START READING NOTES Contents of This Topic SESSION 02 The System Unit Inside the System Unit? Motherboard Power supply Central processing unit(CPU) Random access memory (RAM) Hard disk drive Adapter cards Optical drives Fan Ports Physical components of Computer System(Hardware) can be categorized into four types: Computer System Components Input devices Some of the popular input devices are: The commonly used Input devices are: Mouse has three parts namely Operations/skills/techniques of using mouse A standard computer Keyboard has 101,105,107 or 108 keys Most keyboards have keys arranged in five groups: Output devices Some of the popular output devices are: Common output devices are: Processing devices CPU Storage devices Examples of Storage Devices: Factors that Impact a Computer’s Performance SESSION 02 UTILIZE BASIC CONCEPTS OF COMPUTER SYSTEM IN OPERATING A COMPUTER The System Unit This is a container that houses most of the electronic components that make a computer system. System unit act as a Computer case Alternatively called a box, main unit, and system box, a system unit is the case containing all the main parts of a computer. Inside the System Unit? Motherboard Power Supply Central Processing Unit (CPU) Random-access Memory (RAM) Hard Disk Drive / Solid State Drive Adapter Cards(Sound card, Video card(Graphic card),Network card Optical Drives Fan Ports Bus (Address bus, I/O bus, Memory bus and CPU bus) Motherboard A motherboard is the main circuit board inside a computer that connects the different parts of a computer together. Power supply A power supply is a component that supplies power inside the computer. Central processing unit(CPU) Is the brain of the computer. Or is the part of the computer that handles all operation on the computer system. Random access memory (RAM) Is a computer's primary(temporary) memory, where the data that the processor is currently using is stored. Store data when computer is ON and loose data when computer is OFF. Hard disk drive Is a computer's long-term memory(permanent memory), where the data are stored. Adapter cards Is a type of computer hardware used to add more functions and capabilities to a computer. Video card Sound card Network card Optical drives Is a computer disk drive that uses laser beam technology to read and write data on optical disks like CDs, DVDs, and BDs (Blu-ray discs) Fan A fan is a hardware device that keeps the overall computer or a computer device cool by circulating air to or from the computer or component Ports A port is a connection or a jack provided on a computer to connect external or peripheral devices to the computer Bus A bus is a communication system that transfers data between components inside a computer, or between computers. Physical components of Computer System(Hardware) can be categorized into four types: Input devices Output devices Processing devices and Storage devices Types of Computer Hardware Computer System Components Remember: All types of computers follow the same basic logical structure and perform the basic operations for converting raw input data into information useful to their users. Input Devices Processing Devices Output Devices Storage Devices Input devices Definition- Are devices that are used to enter data in a computer. Functionality. -To translate data from human understanding form to computer understanding form (Computer Readable form) Some of the popular input devices are: Keyboard Mouse Scanner Joystick Light Pen Digitizer Microphone Magnetic Ink Character Recognition (MICR) Optical Character Reader (OCR) Digital Camera Paddle Steering Wheel Gesture recognition devices Light Gun Touch Pad Remote Touch screen VR Webcam Biometric Devices The commonly used Input devices are: Keyboard Mouse Mouse has three parts namely Left click Right click Scroll Types of the mouse Wired mouse Wireless mouse Optical mouse Operations/skills/techniques of using mouse Point: When you’re told to “point the mouse,” you move the mouse on the desktop, which moves the mouse pointer on the screen to point at something interesting (or not). Click: A click is a press of the mouse button — one press and release of the main button, the one on the left. Clicking is often done to select something or to identify a specific location on the screen. Right-click: This action is the same as a click, although the right mouse button is used to get more commands. Double-click: This one works just like the single click, although you click twice in the same spot — usually, rather rapidly. Drag: The drag operation is done to graphically pick up something on the screen and move it. A standard computer Keyboard has 101,105,107 or 108 keys The layout/Features of the Keyboard Most keyboards have keys arranged in five groups: Function keys Numbering keys Alphabetic keys Symbols/Commanding keys Special keys Output devices Definition – Are devices that are used to give results of the processed information. Functionality Translates data from computer understanding form to human understanding form Some of the popular output devices are: Monitor Printer Headphones Computer Speakers Projector GPS Sound Card Video Card Braille Reader Speech-Generating Device Common output devices are: Printer Monitor Speaker Projector Which are Input Devices and which are Output Devices? Processing devices Definition – Are devices that are used to process data and handle all computer operations. Functionality It handles all operations on the computer system Some of the popular processing devices are: CPU (central processing unit) GPU (graphics processing unit) CPU Function of CPU 1. Fetch: gets an instruction from memory 2. Decode: decides/interpret what the instruction means 3. Execute: performs the instruction Storage devices Definition – Are devices that are used to store data and all programs. This devices act as Computer Memory Types of Computer Memory: Primary Memory (Main memory) Is the memory that holds data, programs and instructions that are currently in use. Secondary Memory Computer memory that stores data and programs permanent. Examples of Storage Devices: One that act as Primary memory: Read only memory (ROM) Random access memory (RAM) One that act as Secondary memory: Magnetic Tape Hard Disk drive Optical Storage i.e CD and DVD Solid State

OPTOMETRY · SEMESTER 1 Introduction to Computers Computer Applications START READING NOTES Contents of This Topic INTRODUCTION TO BASIC COMPUTERS LEARNING OBJECTIVES – What is a Computer? The history of Computer The History of Computer cont.… The History of Computer cont… CHARACTERISTICS OF A COMPUTER Other Characteristics are: CLASSIFICATION OR TYPES OF COMPUTERS TYPES OF COMPUTER BASED ON SIZE Types of computer based on size cont.….. Picture of a Supercomputer 1.Types of computer based on size cont.… Picture of a Mainframe computer. 1.Types of computer based on size cont.…. 2. Types of computer based on Generation 3.Types of computer based on Purposes 4. Types of computer based on Technology The Parts of a Computer System HARDWARE SOFTWARE DATA Types of Hardware The CPU (PROCESSOR) Memory How Memory is Measured Input and Output Devices Storage Devices What is Software? System Software Application Software Differences between System software and application software Computer device connections Computer Booting Management of Folders and Files Any question INTRODUCTION TO BASIC COMPUTERS SESSION 1 1 LEARNING OBJECTIVES By the end of this session, you should be able to: Define computer Explain the history of computer Outline characteristics of computer Identify types of computers according to size, generation, purpose/function, technology Identify structure/anatomy of computer (input, CPU, and output) Identify components of a computer (Hardware and Software) Explain types of computer software Explain types of computer hardware (processing, input, output storage Perform computer device connections Perform computer booting (cold and warm booting) Manage folders and files (create, rename, delete, restore, copy, move, search, organize and transfer from computer to removable storage devices) 2 – What is a Computer? Computer is an electronic device used to process data. Computer can convert data into information that is useful to people. OR Computer: is an electronic device that takes data, stores it, processes that data and produces information. Computer: is a machine or device which accepts data in one form and processes it to produce an output of information. Data: can be defined as unprocessed facts/Raw facts . 3 The history of Computer Mechanical era: In the 19th century, Charles Babbage designed the analytical engine, a programmable mechanical computer, and Ada Lovelace wrote the first algorithm for it. First electronic computers: The ENIAC, considered the first programmable electronic computer, was completed in the 1940s. 4 The History of Computer cont.… 1. First Generation (1940–1956) – Vacuum Tubes: Used vacuum tubes for processing. Very large, consumed a lot of power, and produced much heat. Programming was done in machine language. Example: ENIAC, UNIVAC I. 2. Second Generation (1956–1963) – Transistors: Replaced vacuum tubes with transistors Smaller, more reliable, and faster. Used assembly language. Example: IBM 1401. 5 The History of Computer cont… 3. Third Generation (1964–1971) – Integrated Circuits (ICs): Used ICs (multiple transistors on a chip). Increased processing speed and efficiency. Used high-level languages like COBOL, FORTRAN. Computers became more accessible to businesses. 4. Fourth Generation (1971–1980) – Microprocessors: Introduced the microprocessor (entire CPU on a single chip). Rise of personal computers (PCs). Increased power, speed, and storage. Example: Intel 4004, Apple I, IBM PC. 6 The History of Computer cont… 5. Fifth Generation (1980-Present) – AI & Advanced Technologies: This era is characterized by the rise of personal computers, the internet, and the integration of artificial intelligence and other advanced technologies. In this Modern era: Computers have become smaller and more powerful, evolving into laptops, smartphones, and wearable devices. 7 CHARACTERISTICS OF A COMPUTER THE TWO PRINCIPAL CHARACTERISTICS OF COMPUTER ARE:- A computer responds to a specific set of instructions in a well-defined manner. A computer can execute a pre-recorded list of instructions (a program). 8 Other Characteristics are: SPEED : Computer can perform millions of instructions per second.. ACCURACY : Since Computer is programmed, so what ever input we give it gives accurate results. STORAGE : Computer can store mass storage of data with appropriate format. DILIGENCE : Computer Doesn’t get tired or lose concentration. VERSATILITY : Computer can perform different types of tasks at the same time. NO IQ : Computer does not work without instruction. NO FEELING : Computer does not have emotions, knowledge, experience AUTOMATION: Computer Works automatically after programming. 9 CLASSIFICATION OR TYPES OF COMPUTERS We can classify types of computers based on the following criteria:- Types of computer Based on size Types of computer Based on generation Types of computer Based on purposes/function Types of computer Based on Technology 10 TYPES OF COMPUTER BASED ON SIZE Supercomputer Mainframe Minicomputer Workstation Microcomputer 11 Types of computer based on size cont.….. 1. Supercomputer It is Extremely fast, used for scientific simulations, weather forecasting and space exploration. It is Very accurate It has High processing speed Can tackle complex tasks such as breaking codes and modeling worldwide weather system. An example of supercomputer: IBM Deep Blue 12 Picture of a Supercomputer 13 1.Types of computer based on size cont.… 2. Mainframe These are the very largest computers; they can occupy more than one room. For example: IBM 370, S/390. A powerful multi-user computer capable of supporting many hundreds or thousands of users simultaneously like ATM Transactions. They are: Large in size Expensive due to high cost of production High storage capacity and high processing speed Used in organization to process a bulk of information Generally used by large businesses to provide centralized storage, Processing and management for large amounts of data. 14 Picture of a Mainframe computer. 15 1.Types of computer based on size cont.…. 3. Minicomputer A multi-user computer: Smaller than mainframe but more powerful than Micro-computer. computers that are capable of supporting from 10 to hundreds of users simultaneously. These are large powerful machines typically serving a network of simple terminals. Example of minicomputer; Digital Alpha, Sun Ultra, HP 3000 series, IBM AS/400,PDP series. Very powerful and expensive Used in medium scale organizations where it is too expensive to use mainframe computers 16 1.Types of computer based on size cont.… 4. Workstation Powerful desktop computers designed for specialized tasks such as medical imaging. Such tasks