Unit 1_L1.pdf

1 Unit 1 : Introduction to Operating System Lecture 1 Manojeet Roy School of Computer Science UPES, Dehradun India  Table of Contents 1. Computer Hardware Review 2. Computer System 3. I...

1 Unit 1 : Introduction to Operating System Lecture 1 Manojeet Roy School of Computer Science UPES, Dehradun India  Table of Contents 1. Computer Hardware Review 2. Computer System 3. Introduction to Operating System 3.1. Definition 3.2. Operating System view  Learning & Course Outcomes Learning Outcomes LO1:Understand the functions of major computer hardware components LO2: Define an operating system and identify its types and functions Course Outcomes CO1: Demonstrate a comprehensive understanding of operating systems  Computer Hardware Review Computer hardware includes the physical parts of a computer, such as a Cabinet, central processing unit (CPU), random access memory (RAM), monitor, and mouse which processes the input according to the set of instructions provided to it by the user and gives the desired output. A Computer is comprised of two major components 1. Hardware 2. Software Fig 1. Components of Computer  Computer Hardware Review Computer hardware is a physical device of computers that we can see and touch. Hardware Components Monitor Central Processing Unit Mouse Joystick Etc Fig 2. Hardware Components Using these devices, we can control computer operations like input and output. These hardware components are further divided into the following categories: Hardware Categories Input Devices Output Devices Storage Devices Internal Components Fig 3. Hardware Categories  Computer Hardware Review Input Devices Input devices are those devices with the help of which the user interacts with the computer. 1. Keyboard 2. Mouse 3. Scanner 4. Light Pen Keyboard Mouse Scanner Light Pen Bar Code Reader 5. Bar Code Reader etc. Fig 4. Input Devices Output Devices These are the devices that are used to display the output of any task given to the computer in human- readable form. 1. Monitor 2. Printer 3. Speaker etc. Monitor Printer Speaker Fig 5. Output Devices  Computer Hardware Review Internal Components 1. CPU (Central Processing Unit): Its also known as the heart of the computer. It consists of three units, generally known as the control unit, Arithmetic Logical Unit (ALU), and the memory unit. Fig 6. Central Processing Unit 2. Mother Board: It contain the main circuit board inside a computer and contains most of the electronic components together. All the components of the computer are directly or indirectly connected to the motherboard. It includes RAM slots, controllers, system chipsets etc. Fig 7. Mother Board  Computer Hardware Review Internal Components 3. RAM (Random Access Memory): It is also known as temporary or volatile memory. It holds the program and data, which are currently in process or processing. Fig 8. Random Access Memory 4. Power Supply All of a computer system’s parts are powered by a power source. Typically, a power cord is used to connect a computer tower to an electrical outlet. Fig 9. Power Supply  Computer Hardware Review Internal Components 5. Cooling Fan A computer’s system to prevent overheating uses cooling fans. To aid customers who use their computers intensively, such as when streaming video or playing games, many computers contain more than one cooling fan. 6. Hard Drive Fig 10. Cooling Fan On a computer system, files, programs, and other types of information are stored on hard drives, which are data storage devices. They utilise hard drives, which are magnetically coated discs used to store digital versions of information. A computer technician can suspect a corrupt hard disk when a hard drive dies. Fig 11. Hard Disk  Computer System Computer system consists of hardware components that have been carefully chosen so that they work well together and software components or programs that run in the computer. The main software component is itself an operating system (OS) that manages and provides services to other programs that can be run in the computer. In its most basic form, a computer system is a programmable electronic device that can accept input; store data; and retrieve, process and output Fig 12. A modern computer system. information.  Introduction to Operating System: Definition Operating system can be defined in several ways: An Operating System (OS) is a system software which is a collection of software that manages computer hardware resources and provides common services for computer programs. The operating system is the most important type of system software in a computer system. An operating system is like a bridge between your computer’s hardware and the programs you use. It makes sure that your computer’s memory, CPU, and storage are used effectively while running. Operating System is a fully integrated set of specialized programs that handle all the operations of the computer. It controls and monitors the execution of all other programs that reside in the computer, which also includes application programs and other system software of the computer. Examples of Operating Systems are Windows, Linux, Mac OS, etc.  Operating System: View An operating system can be defined or observed in two ways User View System View User View The user viewpoint focuses on how the user interacts with the operating system through the usage of various application programs. In contrast, the system viewpoint focuses on how the hardware interacts with the operating system to complete various tasks. Single User Viewpoint Multiple User Viewpoint User Viewpoint Handled User Viewpoint Embedded User Viewpoint  Operating System: User Viewpoint Single User These systems are designed for a single user experience and meet the needs of a single Viewpoint user The performance is not given focus as the multiple user systems. Fig 13. Single User Viewpoint  Operating System: User Viewpoint These systems consists one mainframe computer and many users on their computers trying to Multiple User interact with their kernels over the mainframe to each other. Viewpoint In such systems, memory allocation by the CPU must be done effectively to give a good user experience. The client-server architecture is another good example where many clients may interact through a remote server Fig 14. Multiple User Viewpoint  Operating System: User Viewpoint Handled User These systems are lies under touchscreen era that comes with best handheld Viewpoint technology ever. Smartphones interact via wireless devices to perform numerous operations, Such operating system is a great example of creating a device focused on the user's point of view. Systems in which remote control used to turn on or off the tv is all part of an Embedded User embedded system in which the electronic device communicates with another Viewpoint program where the user viewpoint is limited and allows the user to engage with the application.  Operating System: View An operating system can be defined or observed in two ways User View System View System View A computer system comprises various sources, such as hardware and software, which must be managed effectively. The operating system manages the resources, decides between competing demands, controls the program execution, etc. According to this point of view, the operating system's purpose is to maximize performance. The operating system is responsible for managing hardware resources and allocating them to programs and users to ensure maximum performance. Resource Allocation System Viewpoint Control Program  Operating System: System Viewpoint From a system viewpoint, the hardware interacts with the operating system than with the user. The hardware and the operating system interact for a variety of reasons, including: The hardware contains several resources like registers, caches, RAM, ROM, CPUs, I/O Resource Allocation interaction, etc. These are all resources that the operating system needs when an application program demands them. Only the operating system can allocate resources with several tactics and strategies to maximize its processing and memory space. The operating system uses a variety of strategies to get the most out of the hardware resources, including paging, virtual memory, caching, and so on. The control program controls how input and output devices (hardware) interact with the Control Program operating system. The user may request an action that can only be done with I/O devices; in this case, the operating system must also have proper communication, control, detect, and handle such devices. Computer Components: Top Level View  MCQ Q1. Which of the following is NOT an input device? A. Keyboard B. Mouse C. Monitor D. Scanner Q2. What is the main function of the CPU in a computer system? A. To display output B. To manage software resources C. To process input according to instructions D. To store data permanently Q3. The component that holds most of the electronic components together and connects all parts of the computer is called: A. Hard Drive B. Motherboard C. Power Supply D.RAM Q4. RAM is classified as which type of memory. A. Permanent B. Volatile C. Non-volatile D. External  MCQ Q5. The primary function of an operating system is to: A. Manage computer hardware resources B. Provide antivirus protection C. Design graphics D. Develop software Q6. An operating system that allows multiple users to interact with a mainframe computer is an example of: A. Single User System B. Multiple User System C. Handled User System D. Real-Time System Q7. The user viewpoint of an operating system focuses on: A. How hardware interacts with the OS B. How the user interacts with application programs C. Resource allocation D. Control program functions Q8. The operating system uses strategies like paging and virtual memory for: A. Resource allocation B. Managing user interfaces C. Controlling I/O devices D. Executing application programs  MCQ: Answers Question No- Answers Option Description Q1- Answer C Monitor Q2- Answer C To process input according to instructions Q3- Answer B Motherboard Q4- Answer B Volatile Q5- Answer A Manage computer hardware resources Q6- Answer B Multiple User System Q7- Answer B How the user interacts with application programs Q8- Answer A Resource allocation  Summary/Key Points Computer hardware includes the physical parts of a computer, such as a Cabinet, central processing unit (CPU), random access memory (RAM) etc. Computer Hardware is categorized into 4 categories i.e., Input Devices, Output devices, Storage Device, Internal Components Computer system consists of hardware components that have been carefully chosen so that they work well together and software components or programs that run in the computer. An Operating System (OS) is a system software which is a collection of software that manages computer hardware resources and provides common services for computer programs. The operating system is the most important type of system software in a computer system. An operating system can be defined two ways: User View & System View  Reference Material Operating Systems Concepts (10th Ed.) Silberschatz A, Peterson J and Galvin P, John Wiley & Sons, Inc. 2018. Computer Hardware Review, Page No: 1-3 Computer System, Page No: 3-4 Operating system view, Page No: 3-4 Modern Operating Systems (4th Ed.) by Andrew S. Tanenbaum and Herbert Bos, 2007 Operating Systems: Principles and Practice by Thomas Anderson and Michael Dahlin, 2014  Coming Up-Next Lecture History of Operating System Types of Operating Functions of Operating System Thank You 26