Lecture 1 - Windows operating system concepts.pptx

operating systems basics

1. Class Expectations Class participation – Your input is needed for good discussion Keep up with reading material Complete assignments and projects on time Submit clean, organized, and concise work Brush up prior knowledge Follow academic integrity code Iragaba john 3/30/2022

2. Lecture Etiquette Be on time (if you are late enter the class quietly) Your ring-tone is not that great! ( cell phones off or muted) You can do without Facebook / YouTube / twitter for 2-3hrs - If you have to, don ’ t disturb your peers Interrupt for questions – there is no dumb question Iragaba john 3/30/2022

3. Key to Success Attendance Pay attention to lecturers and keep extra notes Ask questions Effort Do homework on your own. It ’ s ok to ask others, but make your own effort Read extra material on your own. Wealth of information available (library books, online articles, research papers) Consistency Keep up with the class pace Iragaba john 3/30/2022

4. INTRODUCTION TO OPERATING SYSTEMS Iragaba john 3/30/2022

5. Overview of a computer A computer is an electronic device that manipulates information, or "data." It has the ability to store , retrieve , and process data. You can use a computer to type documents, send email, and surf the Internet . You can also use it to handle spreadsheets, accounting, database management, presentations , games, and more. Iragaba john 3/30/2022

6. Overview Cont’d Whether you realize it or not, computers play an important role in our lives ; When you withdraw cash from an ATM, scan groceries at the store, or use a calculator, you're using a type of computer. All types of computers consist of two basic parts: • Hardware is any part of your computer that has a physical structure , such as the computer monitor or keyboard. • Software is any set of instructions that tells the hardware what to do. It is what guides the hardware and tells it how to accomplish each task. Some examples of software are web browsers, games, and word processors. Iragaba john 3/30/2022

7. Overview Cont’d Software is grouped into: User software User applications Editors Compilers Shells System Software Operating System Iragaba john 3/30/2022

8. What is an Operating System? An operating system is a program that acts as an intermediary between the user of a computer and the computer hardware. It is a software program that manages the hardware and software resources of a computer. The purpose of an operating system is to provide an environment in which a user can execute programs in a convenient and efficient manner . The operating system must ensure the correct operation of the computer system. Iragaba john 3/30/2022

9. What is an Operating System? Cont’d Operating systems have been developed over the past 45 years for two main purposes. First , the operating system attempts to schedule computational activities to ensure good performance of the computing system. Second , it provides a convenient environment for the development and execution of programs Iragaba john 3/30/2022

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12. The History of Operating Systems The first computers did not have operating systems. However, software tools for managing the system and simplifying the use of hardware appeared very quickly afterwards, and gradually expanded in scope . “Preparing ENIAC for a series of runs was an incredibly involved process . First, detailed instructions had to be written defining the problem and a procedure for solving it. These instructions were programmed by adjusting switches manually and inserting thousands of cables into as many as forty large plug boards . A team of five operators might work several days on the external wiring and many more days searching for errors and correcting them .” Iragaba john 3/30/2022

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14. History Cont’d By the early 1960s, commercial computer vendors were supplying quite extensive tools for streamlining the development, scheduling, and execution of jobs on batch processing systems. Examples were produced by UNIVAC and Control Data Corporation, amongst others. Through the 1960s, several major concepts were developed, driving the development of operating systems. The development of the IBM System/360 produced a family of mainframe computers available in widely differing capacities and price points, for which a single operating system OS/360 was planned Iragaba john 3/30/2022

15. History Cont’d Another key development was the concept of time-sharing: the idea of sharing the resources of expensive computers amongst multiple computer users interacting in real time with the system. Time sharing allowed all of the users to have the illusion of having exclusive access to the machine; the Multics timesharing system was the most famous of a number of new operating systems developed to take advantage of the concept . Multics , particularly, was an inspiration to a number of operating systems developed in the 1970s , notably Unix. Another commercially-popular minicomputer operating system was VMS. The first microcomputers did not have the capacity or need for the elaborate operating systems that had been developed for mainframes and minis; minimalistic operating systems were developed. One notable early operating system was CP/M, which was supported on many early microcomputers and was largely cloned in creating MS-DOS, which became wildly popular as the operating system chosen for the IBM PC Iragaba john 3/30/2022

16. History Cont’d By the 1990s, the microcomputer had evolved to the point where, as well as extensive GUI facilities , the robustness and flexibility of operating systems of larger computers became increasingly desirable . Microsoft's response to this change was the development of Windows NT, which served as the basis for Microsoft's entire operating system line starting in 1999. Apple rebuilt their operating system on top of a Unix core as Mac OS X, released in 2001. Hobbyist-developed reimplementations of Unix, assembled with the tools from the GNU project, also became popular; versions based on the Linux kernel are by far the most popular, with the BSD derived UNIXes holding a small portion of the server market . Today Command line interface (or CLI) operating systems can operate using only the keyboard for input . Modern OS's use a mouse for input with a graphical user interface (GUI) sometimes implemented as a shell. The appropriate OS may depend on the hardware architecture, specifically the CPU, with only Linux and BSD running on almost any CPU Iragaba john 3/30/2022

17. Types of operating systems The 2 major types of operating systems are : Standalone OS / Desktop OS Single user OS which are generally used by personal users for desktop applications, e.g. DOS, Windows 3x, Windows 9x, Windows xp, windows 7, etc. Network OS They are multi-user and time-sharing OS. The entire network operating system support multiprocessing and multitasking features, e.g. UNIX, Novell, Windows NT, Windows 2000/2003/2005/2008 server, etc. Iragaba john 3/30/2022

18. Compare Operating Systems Terms often used when comparing operating systems: Multi-user – Two or more users can work with programs and share peripheral devices, such as printers, at the same time. Multi-tasking – The computer is capable of operating multiple applications at the same time. Multi-processing – The computer can have two or more central processing units (CPUs) that programs share. Multi-threading – A program can be broken into smaller parts that can be loaded as needed by the operating system. Multi-threading allows individual programs to be multi-tasked. Iragaba john 3/30/2022

19. Compare Operating Systems Cont’d Desktop Operating System Supports a single user Runs single-user applications Shares files and folders Shares peripherals Used on a small network Supports multiple users Runs multi-user applications Is robust and redundant Provides increased security Used on a network Network Operating System

20. Standalone / Desktop OS Desktop operating systems: Microsoft Windows: Windows XP Macintosh: Mac OS X Linux: Fedora, Ubuntu, and others UNIX : free BSD A desktop OS has the following characteristics: Supports a single user Runs single-user applications Shares files and folders on a small network with limited security Iragaba john 3/30/2022

21. Network Operating Systems (NOS) Common NOS include: Novell Netware Microsoft Windows Server Linux UNIX A network OS has the following characteristics: Supports multiple users Runs multi-user applications Is robust and redundant Provides increased security compared to desktop operating systems Iragaba john 3/30/2022

22. Roles of an Operating System All computers rely on an operating system (OS) to provide the interface for interaction between users, applications, and hardware. The operating system boots the computer and manages the file system. Almost all modern operating systems can support more than one user, task, or CPU. The operating system has four main roles: Control hardware access Manage files and folders Provide user interface Manage applications Iragaba john 3/30/2022

23. Roles of an Operating System Cont’d Control hardware access - The operating system manages the interaction between applications and the hardware. To access and communicate with the hardware, the operating system installs a device driver for each hardware component. A device driver is a small program written by the hardware manufacturer and supplied with the hardware component. The process of assigning system resources and installing drivers can be performed with Plug and Play (PnP). The operating system automatically detects the PnP-compatible hardware and installs the driver for that component. The operating system then configures the device and updates the registry, which is a database that contains all the information about the computer. NOTE: The registry contains information about applications, users, hardware, network settings, and file types. Manage files and folders - The operating system creates a file structure on the hard disk drive to allow data to be stored. A file is a block of related data that is given a single name and treated as a single unit. Program and data files are grouped together in a directory. The files and directories are organized for easy retrieval and use. Directories can be kept inside other directories. These nested directories are referred to as subdirectories. Directories are called folders in Windows operating systems, and subdirectories are called subfolders. Iragaba john 3/30/2022

24. Roles of an Operating System Cont’d User interface - The operating system enables the user to interact with software and hardware. There are two types of user interfaces: Command Line Interface (CLI) – The user types commands at a prompt. Graphical User Interface (GUI) – The user interacts with menus and icons. Most operating systems, such as Windows 2000 and Windows XP, include both a GUI and a CLI. Application management - The operating system manages all programs to ensure that the correct resources are allocated to the applications. The operating system locates an application and loads it into the RAM of the computer. Applications are software programs, such as word processors, databases, spreadsheets, games, and many other applications. The operating system ensures that each application has adequate system resources. Application programming interface (API) is a set of guidelines used by programmers to ensure that the application they are developing is compatible with an operating system . Iragaba john 3/30/2022

25. Characteristics of Operating Systems Control hardware access OS automatically discovers and configures the PnP hardware File and folder management User interface Command line interface (CLI) Graphical user interface (GUI) Application management Open Graphics Library (OpenGL) DirectX Iragaba john 3/30/2022

26. Types of Operating System Interfaces Graphical User Interface (GUI): The user interacts with menus and icons. Command Line Interface (CLI): The user types commands at a prompt. Most operating systems include both a GUI and a CLI. The User Interface (UI) is the component of the OS that the user interacts with. The UI is like an interpreter, translating user keystrokes, mouse clicks, or other input for the appropriate programs. Iragaba john 3/30/2022

27. Operating systems requirements Operating systems require a certain amount of hardware resources. These resources are specified by the manufacturer and include such things as: Amount of RAM Hard disk space required Processor type and speed Video resolution Manufacturers often specify both a minimum and recommended level of hardware resources. System performance at the minimum specified hardware configuration is usually poor and only sufficient to support the OS and no other functionality. The recommended configuration is usually the better option and is more likely to support standard additional applications and resources. Iragaba john 3/30/2022

28. End of Lecture 1 T hanks Iragaba john 3/30/2022