# Information Systems/Operating Systems

An operating system (OS) is a collection of software that manages computer hardware resources and provides common services for computer programs. The operating system is a vital component of the system software in a computer system. Application programs usually require an operating system to function.

## Objectives and Skills

Objectives and skills for the operating systems portion of CLEP Information Systems include:
* Concepts of computer architectures (mainframe, client/server, operating systems)
* Basic user functions of a desktop operating system (memory management, file management, interfaces, types of OS)

## Readings

* Wikibooks: Introduction to Computer Information Systems/System Software
* Wikipedia: Operating system
* Wikipedia: 64-bit_computing#32-bit_vs_64-bit
* Wikihow: How to pick an Operating System
* Linux Disti-Breakdown

## Multimedia

* Operating Systems - Crash Course Computer Science
* YouTube: Operating System Functions
* YouTube: Types of Operating Systems
* YouTube: The History of Operating Systems
* YouTube: What Are Bits, and Are They Important?
* YouTube: Windows 10 updates
* YouTube: what is an Operating system as Fast As possible
* YouTube: Computer Basics: Understanding Operating Systems
* YouTube: Types of Operating Systems; Explained in Short Time
* YouTube: Basics of OS Computer System Operation
* YouTube: Split view: Mac vs Windows 10
* YouTube: Operating System Basics

## Activities

* Complete the tutorial GCFLearnFree: Understanding Operating Systems.
* Determine whether your computer is running a 32 or 64-bit operating system:
** Windows: Review Microsoft: Is my PC running the 32-bit or 64-bit version of Windows?.
** macOS: Review Apple: macOS: 64-bit kernel frequently asked questions.
** Chrome OS: Settings tab, About Chrome OS; Copy link: chrome://settings/help
** Linux: Review Uname Run uname -m to see system information such as 32-bit or 64-bit.
* Use your system's monitoring utilities to review active processes and resources in use:
** Windows: Review Wikipedia: Windows Task Manager and Wikipedia: Resource Monitor and run both utilities.
** macOS: Review Wikipedia: Activity Monitor and run the utility.
** Linux: Review Top. Run top to see current system utilization of cpu, memory, swap, and processes.
* Review Wikipedia: Device Manager and Microsoft: Update a driver for hardware that isn't working properly. Run Device Manager on a Windows system Use Device Manager to check for updated drivers for all display adapters, network adapters, and sound controllers.
* Examine system health and recent events for your system:
** Windows: Review Microsoft: How to Use Reliability Monitor and Wikipedia: Event Viewer and run the utilities.
** macOS: Review Wikipedia: Console (macOS) and run the utility.
* Try out any of these Tips and Tricks on Windows 10
* Identify your operating system version:
** Windows: Use the Start menu and run winver.
** Linux: Open a Terminal window and run lsb-release -a.
** macOS: Select the Apple icon in the top left corner of your screen and select About this MAC.
* Test operating systems:
** Windows: MIT: Windows 10 Simulator
** macOS: alessioatzeni.com: Mac OSX Lion CSS3
** Linux: Download and install VNC Viewer and then test different Linux distributions using distrotest.net. Popular Linux desktop distributions include Ubuntu, Linux Mint, and Fedora.
* VirtualBox - Software - This link will take you to the Oracle VM VirtualBox software - you can download this for free and essentially "make your own machine" virtually to test out different components of a device - higher skill level recommended.

## Research and Discussion

* Research operating systems in use in your work and personal environments. Consider server-based systems, personal computers, tablets, smartphones, and wearable devices. Are the operating systems proprietary or open-source? Does each provider charge for the operating system? If not, what do they receive in return for their efforts?
* Compare PC-based operating systems (Windows, macOS, Unix/Linux) and mobile operating systems (Android, ChromeOS, iOS). Describe advantages and disadvantages of each. Which operating system(s) do you prefer, and why.
* Research and compare different PC-based operating system functions. What is the purpose between the operating system and the computer hardware? Describe a few tasks that you frequently perform using your operating system, and why.

## Lesson Summary

* An operating system is a software that manages computer hardware and software resources and provides common services for computer programs. Operating systems are crucial to system software as most applications require an OS to run..
* The operating system allows you to communicate with the computer without knowing how to speak the computer language. The basic goal of an operating system is to carry out user programs and make the burden easier. In other words, it provides an interface between the user and the system.
* Hardware functions such as input & output and memory allocation, the operating system acts as an intermediary between application programs and the computer hardware.
* The operating system coordinates all of the hardware and software components on the computer to make sure each program gets what it needs..
* The operating system provides an environment for software applications like spreadsheets, word processors and database programs to function. For instance, word processors create, edit, save and print documents.
* The operating system monitors system health and functionality of the computer by providing a file structure for data management.
* Popular computer operating systems include Windows, macOS/macOS, Linux, and Chrome OS, with Windows 7 being the most popular operating system for desktop and laptops.
* A mobile operating system, also referred to as mobile OS, is an operating system that operates a smartphone, with Android being the most popular smartphone operating system and IOS as the most popular tablet operating system, PDA, or other mobile devices.
* macOS, Linux, Android, Chrome OS, and iOS are based on Unix. iOS is based on macOS which is, itself, a variant of a BSD UNIX kernel running on top of a micro kernel called Mach., https://www.quora.com/Is-iOS-based-on-Linux-kernel-In-this-case-is-it-possible-to-install-a-Linux-program-in-an-iPhone-for-example-a-node-js-server.
* Popular distributions of Linux include Red Hat, Debian, Ubuntu, Linux Mint and Google's Android.
* Open-source software is computer software with its source code made available with a license in which the copyright holder provides the rights to study, change and distribute the software to anyone and for any purpose.. Examples of the open-source software include internet browsers like Mozilla Firefox, LibreOffice and Google Chrome.[source?]
* Proprietary software or closed source software is computer software licensed under exclusive legal right of the copyright holder with the intent that the licensee is given the right to use the software only under certain conditions, and restricted from other uses, such as modification, sharing, studying, redistribution, or reverse engineering.
* A real-time operating system (RTOS) is an operating system intended for applications with fixed deadlines (real-time computing). This is completed by a core switching rapidly between tasks without buffer delays.

## Key Terms
### 32-bit

    A computer architecture that supports at most 32-bit integers, memory addresses, and other data units, limiting integer values to -2,147,483,648 through 2,147,483,647 and memory addresses to 4 GiB (gigabytes or gibibytes).

### 64-bit

    A computer architecture that supports at most 64-bit integers, memory addresses, and other data units, limiting integer values to over 18 quintillion and memory addresses to 16 EiB (exbibytes).

### agent

    A computer program that acts on behalf of a user or other program.

### Android

    A mobile operating system (OS) based on the Linux kernel and currently developed by Google.

### BlackBerry OS

    A proprietary mobile operating system developed by BlackBerry Ltd for its BlackBerry line of smartphone handheld devices.

### booting

    The initialization of a computerized system.

### command-line interface (CLI)

    A means of interacting with a computer program where the user issues commands to the program in the form of successive lines of text.

### compatibility

    The ability to run software on a given system.

### copyright

    Used by proprietary software companies to prevent the unauthorized copying of their software and by open source licenses to enforce their terms.

### cross-platform

    An attribute conferred to computer software or computing methods and concepts that are implemented and inter-operate on multiple computer platforms.

### daemon

    A daemon is a long-running computer program that runs as a background process. Examples of this would be inted, httpd, mysqld, and snmpd.

### device driver

    A computer program that operates or controls a particular type of device that is attached to a computer, specifically hardware devices

### disk operating system (DOS)

    An acronym for several computer operating systems that were operated by using the command line.

### end-user license agreement (EULA)

    The contract between a licensor and purchaser, establishing the purchaser's right to use software.

### file manager

    A computer program that provides a user interface to manage files and folders.

### formatting

    The process of preparing a data storage device such as a hard disk drive, solid-state drive, floppy disk or USB flash drive for initial use.

### fragmentation

    Occurs when a file system cannot or will not allocate enough contiguous space to store a complete file as a unit, but instead puts parts of it in gaps between existing files.

### Google Chrome OS

    An operating system based on the Linux kernel and designed by Google to work with web applications and installed applications, initially designed as a pure web thin client operating system.

### Graphical User Interface (GUI)

    A type of interface that allows users to interact with electronic devices through icons and visual indicators such as secondary notation, instead of text-based user interfaces, typed command labels or text navigation.

### iOS

    A mobile operating system developed by Apple Inc. and distributed exclusively for Apple hardware, including iPods, iPhones, and iPads.

### kernel

    A computer program that manages I/O requests from software, and translates them into data processing instructions for the central processing unit and other electronic components of a computer.

### Linux

    A Unix-like computer operating system assembled under the model of free and open-source software development and distribution.

### macOS

    A series of graphical user interface–based operating systems developed by Apple Inc. for their Macintosh line of computer systems, currently branded as macOS.

### malware (short for malicious software)

    Any software intentionally designed to cause damage to a computer, server or computer network.

### memory management

    Provides ways to dynamically allocate portions of memory to programs at their request, and free it for reuse when no longer needed.

### menu bar

    A graphical control element that lists options or commands presented to an operator by a computer or communications system.

### mobile operating system

    An operating system for smartphones, tablets, or other mobile devices (Android, iOS, Windows Phone, and Blackberry).

### multi-tasking

    Performing multiple tasks over a certain period of time by executing them concurrently.

### open source

    Computer software with its source code made available with a license in which the copyright holder provides the right to study, change and distribute the software to anyone and for any purpose.

### operating system

    System software that manages computer hardware and software resources and provides common services for computer programs (Android, iOS, Windows Phone, and Blackberry).

### macOS

    A series of Unix-based graphical interface operating systems developed and marketed by Apple Inc. designed to run on Mac computers.

### paging

    A memory management scheme by which a computer stores and retrieves data from the secondary storage for use in main memory.

### path

    The general form of the name of a file or directory, specifies a unique location in a file system.

### platform

    Computer hardware architecture, an operating system, and runtime libraries in which a piece of software is designed to run.

### root directory

    The first or top-most directory in a hierarchy.

### real-time operating system (RTOS)

    An operating system intended for applications with fixed deadlines (real-time computing). Such applications include some small embedded systems, automobile engine controllers, industrial robots, spacecraft, industrial control, and some large-scale computing systems.

### safe mode

    A diagnostic mode of a computer operating system (OS).

### shell

    A user interface used to access an operating system's services.

### style

    predefined text formatting available in software applications.[source?]

### task manager

    A system monitor program used to provide information about the processes and programs running on a computer, as well as the general status of the computer.

### taskbar

    An element of a graphical user interface which typically shows which programs or applications are running on the device, as well as providing links or shortcuts to other programs or places.

### Unix

    A family of multitasking, multi-user computer operating systems.

### user interface

    The space where interactions between humans and machines occur.

### virtual memory

    A memory management technique that is implemented using both hardware and software that maps memory addresses used by a program.

### Windows

    A metafamily of graphical operating systems developed, marketed, and sold by Microsoft.

### x64

    The 64-bit version of the x86 instruction set, supporting 64-bit addressing and processing, and fully backwards compatible with 16-bit and 32-bit x86 code.

### x86

    A family of backward compatible instruction set architectures based on the Intel 8086 through 80486 CPUs supporting 16-bit and 32-bit addressing and processing.

### Xbox OS

    The Xbox One system software, sometimes called the Xbox OS, is the operating system for the eighth-generation home video game console, Xbox One.

## Review Questions

* An operating system is _____. An operating system is software that manages computer hardware and software resources and provides common services for computer programs.
* The operating system provides an interface between _____. The operating system provides an Interface between the user and the system.
* The operating system coordinates _____. The operating system coordinates hardware components.
* The operating system provides an environment for _____. The operating system provides an environment for software applications to function.
* The operating system monitors _____. The operating system monitors system health and functionality.
* The operating system provides a file structure for _____. The operating system provides a file structure for data management.
* Popular computer operating systems include _____. Popular computer operating systems include Windows, macOS, Linux, and Chrome OS.
* What kinds of devices use a mobile operating system? A mobile operating system, also referred to as mobile OS, is an operating system that operates a smartphone, tablet, PDA, or other mobile device.
* Name the (4) main mobile operating systems (2 popular, 2 less popular) Popular mobile operating systems include Android, iOS and to a lesser extent Windows Phone and Blackberry.
* Name the (5) operating systems that are based on Unix: macOS, Linux, Android, Chrome OS and iOS are based on Unix.
* Name the (5) popular distributions of Linux: Popular distributions of Linux include Red Hat, Debian, Ubuntu, Linux Mint and Google's Android.
* What is Open-source software? Open-source software is computer software with its source code made available with a license in which the copyright holder provides the rights to study, change and distribute the software to anyone and for any purpose.
* Proprietary software or closed source software is _____. Proprietary software or closed source software is computer software licensed under exclusive legal right of the copyright holder with the intent that the licensee is given the right to use the software only under certain conditions, and restricted from other uses, such as modification, sharing, studying, redistribution, or reverse engineering.
* What does RTOS stand for and its definition: A real-time operating system is an operating system intended for applications with fixed deadlines (real-time computing). Such applications include some small embedded systems, automobile engine controllers, industrial robots, spacecraft, industrial control, and some large-scale computing systems.

## Assessments

* Flashcards: Quizlet: Information Systems - Operating Systems
* Quiz: Quizlet: Information Systems - Operating Systems
* ProProfs Quiz: Introduction to Operating System
* Computer Parts and Operating System Quiz

## See Also

* Computer Software
* Using an Operating System
* IT Fundamentals/Operating Systems
* How Stuff Works: 5 Important Jobs Your Operating System Handles Without You Knowing about it
* How Stuff Works: How Operating Systems Work
* eHow.com: How does a computer operating system work?
* Nash Networks: The Pros and Cons of Operating Systems
* opensource.org: SE Linux A great opensource success story
* linuxquestions.org: Introduction to Linux A hands on guide
* computerworld.com: Is Chrome OS right for you?
* NetMarketShare: OS Market Share
* Bleeping Computer: What is a File Extension?
* TechWorm: Unix Vs. Linux
* Windows, mac or Linux PROS and CONS