Evolution of operating systems classification of desktop applications реферат

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An operating system is the most important software that runs on a computer. It manages the computer's memory and processes, as well as all of its software and hardware. It also allows you to communicate with the computer without knowing how to speak the computer's language. Without an operating system, a сomputer is useless. Watch the video below to learn more about operating systems. Types of operating systems

Operating systems usually come pre-loaded on any computer you buy. Most people use the operating system that comes with their computer, but it's possible to upgrade or even change operating systems. The three most common operating systems for personal computers are Microsoft Windows, Mac OS X, and Linux.

Modern operating systems use a graphical user interface, or GUI (pronounced gooey). A GUI lets you use your mouse to click icons, buttons, and menus, and everything is clearly displayed on the screen using a combination of graphics and text.

Each operating system's GUI has a different look and feel, so if you switch to a different operating system it may seem unfamiliar at first. However, modern operating systems are designed to be easy to use, and most of the basic principles are the same.

Microsoft Windows.Microsoft created the Windows operating system in the mid-1980s. Over the years, there have been many different versions of Windows, but the most recent ones are Windows 10 (released in 2015), Windows 8 (2012), Windows 7(2009), and Windows Vista (2007). Windows comes pre-loaded on most new PCs, which helps to make it the most popular operating system in the world.

Mac OS is a line of operating systems created by Apple. It comes preloaded on all new Macintosh computers, or Macs. All of the recent versions are known asOS X(pronounced O-S Ten), and the specific versions include El Capitan (released in 2015),Yosemite (2014), Mavericks (2013), Mountain Lion (2012), and Lion (2011).

According to Stat Counter Global Stats, Mac OS X users account for less than 10% of global operating systems—much lower than the percentage of Windows users (more than 80%). One reason for this is that Apple computers tend to be more expensive. However, many people do prefer the look and feel of Mac OS X over Windows.

Linux (pronounced LINN-ux) is a family of open-source operating systems, which means they can be modified and distributed by anyone around the world. This is different from proprietary software like Windows, which can only be modified by the company that owns it. The advantages of Linux are that it is free, and there are many different distributions—or versions—you can choose from.

According to StatCounter Global Stats, Linux users account for less than 2% of global operating systems. However, most servers run Linux because it's relatively easy to customize.

To learn more about different distributions of Linux, visit the Ubuntu, Linux Mint, and Fedora websites, or refer to our Linux Mint Resources. For a more comprehensive list, you can visit MakeUseOf's list of The Best Linux Distributions.

Windows is an operating system designed by Microsoft. The operating system is what allows you to use a computer. Windows comes preloaded on most new personal computers (PCs), which helps to make it the most popular operating system in the world.

Windows makes it possible to complete all kinds of everyday tasks on your computer – for example, you can use Windows to browse the Internet, check your email, edit digital photos, listen to music, play games, and do much more.

Timeline of OS Windows

Windows 10 29th july 2015
Windows 8.1 17th October 2013
Windows 8 26th October 2012
Windows 7 22nd October 2009
WindowsVista 30th January 2007
Windows XP Professional x64 25th April 2005
Windows XP 25th October 2001
Windows ME 14th September 2000
Windows 2000 17th February 2000
Windows 98 25th June 1998
Windows 95 24th August 1995
Windows 3.1 April 1992
Windows 3.0 22nd May 1990
Windows 2.11 13th March 1989
Windows 2.10 27th May 1988
Windows 2.03 9th December 1987
Windows 1.04 April 1987
Windows 1.03 August 1986
Windows 1.02 May 1986
Windows 1.01 20th November 1985

Explain the classification of OS

An operating system is the most important software that runs on a computer. Every general-purpose computer must have an operating system to run other programs. It also allows you to communicate with the computer without knowing how to speak the computer's language. It manages the computer's memory, processes, and all of its software and hardware, i.e. manages all the other programs in a computer.

Operating systems perform basic tasks, such as recognizing input from the keyboard, sending output to the display screen, keeping track of files and directories on the disk, and controlling peripheral devices such as disk drives and printers. In addition, users can interact directly with the operating system through a user interface such as a command language or a graphical user interface (GUI).

Classification of Operating systems: Multi-user, Multiprocessing, Multitasking, Multithreading, Real time.

All modern operating systems use a graphical user interface, or GUI (pronounced gooey). A GUI lets you use your mouse to click icons, buttons, and menus, and everything is clearly displayed on the screen using a combination of graphics and text.

The three most common operating systems for personal computers are Microsoft Windows, Apple Mac OS X, and Linux.

An operating system is the program that manages all the application programs in a computer system. This also includes managing the input and output devices, and assigning system resources.

Operating systems evolved as the solution to the problems that were evident in early computer systems, and coincide with the changing computer systems. Three cycles are clear in the evolution of computers, the mainframe computers, minicomputers and microcomputers, and each of these stages influenced the development of operating systems.

Now, advances in software and hardware technologies have resulted in an increased demand for more sophisticated and powerful operating systems, with each new generation able to handle and perform more complex tasks. The following report examines the development of operating systems, and how the changing technology shaped the evolution of operating systems.

First Generation Computers (1945-1955).

In the 1940’s enormous machines capable of performing numerical calculations were created. The machine consisted of vacuum tubes and plugboards, and programming was done purely in machine code. Programming languages were unheard of during the early part of the period, and each machine was specifically assembled to carry out a particular calculation.

These early computers had no need for an operating system and were operated directly from the operator’s console by a computer programmer, who had immediate knowledge of the computers design.

By the early 1950’s punched cards were introduced, allowing programs to be written and read directly from the card, instead of using plugboards.

Second Generation Computers (1955-1965).

In the 1950’s, the transistor was introduced, creating a more reliable computer. Computers were used primarily for scientific and engineering calculations and were programmed mainly in FORTRAN and assembly language.

As computers became more reliable they also became more business orientated, although they were still very large and expensive. Because of the expenditure, the productiveness of the system had to be magnified as to ensure cost effectiveness. Job scheduling and the hiring of computer operators, ensured that the computer was used effectively and crucial time were not wasted.

Loading the compilers was a time consuming process as each compiler was kept on a magnetic tape, which had to be manually mounted? This became a problem particularly when there were multiple jobs to execute written in different languages (mainly in Assembly or Fortran). Each card and tape had to be individually installed executed then removed for each program. To combat this problem, the Batch System was developed. This meant that all the jobs were grouped into batches and read by one computer (usually an IBM 1401) then executed one after the other on the mainframe computer (usually an IBM 7094), eliminating the need to swap tapes or cards between programs.

General Motors designed the first operating system called IBM 701. It was called input/output System, and consisted of a small set of code that provided a common set of procedures to be used to access the input and output devices. It also allowed each program to access the code when finished and accepted and loaded the next program. However, there was a need to improve the sharing of programs, which led to the development of the SOS (Share operating system), in 1959. The SOS provided buffer management and supervision for I/O devices as well as support for programming in assembly language. Around the same time as SOS was being developed, the first operating system to support programming in a high-level language was achieved. FMS (Fortran Monitoring System) incorporated a translator for IBM’s FORTRAN language, which was widely used as most programs where written in this language.

Third Generation Computers (1965-1980).

In the late 1960’s IBM created the System/360 which was a series of software compatible computers ranging in different power of performance and price. The machines had the same architecture and instruction set, which allowed programs written for one machine to be executed on another. The operating system required to run on this family of computers has to be able to work on all models, be backward compatible and be able to run on both small and large systems. The software written to handle these different requirements was OS/360, which consisted of millions of lines of assembly language written by thousands of different programmers. It also contained thousands of bugs, but despite this the operating system satisfactory fulfilled the requirements of most users. A major feature of the new operating system was the ability to implement multiprogramming. By partitioning the memory into several pieces, programmers where able to use the CPU more effectively then ever before, as a job could be processed whilst another was waiting for I/O to finish.

Spooling was another important feature implemented in third generation operating systems. Spooling (Simultaneous Peripheral Operation On-Line) was is ability to load a new program into an empty partition of memory when a pervious job had finished. This technique meant that the IBM 1401 computer was no longer required to read the program from the magnetic tape. Mission of a job and returning of results had increased. This led designers to the concept of time-sharing, which involved each user communicating with the computer through their own on-line terminal. The SPU could only be allocated to 3 terminals, each job held in a partition of memory. Many time-sharing operating systems were introduced in the 1960’s, including the MULTICS (Multiplexed Information and Computing Service). Developed by Bell Labs, MULTICS was written almost completely in high-level language, and is known as the first major operating system to have done so. MULTICS examined many new concepts including segmented memory, device independence, hierarchical file system, I/O redirection, a powerful user interface and protection rings.

The 1960’s also gave rise to the minicomputer, starting with the DEC PDP-1. Minicomputers presented the market with an affordable alternative to the large batch systems of that time, but had only a small amount of memory. The early operating system of the minicomputers were input/output selectors, and provided an interactive user interface for a single user, and ran only one program at a time.

By the 1970’s, DEC introduced a new family of minicomputers. The PDP-11 series had 3 operating systems available to use on the systems, a simple single user system (RT-11), a time sharing system (RSTS) and a real-time system (RSX-11).

RSX-11 was the most advanced operating system for the PDP-11 series. It supported a powerful command language and file system, memory management and multiprogramming a number of tasks.

Around the same time as DEC were implementing their minicomputers, two researchers, ken Thomspson and Dennis Richie were developing a new operating system for the DEC PDP-7. Their aim was to create a new single-user operating, and the first version was officially released in 1971. This operating system, called UNIX became very popular and is still used widely today.

Fourth Generation Computers (1980-1990)

by the 1980’s, technology had advanced a great deal from the days of the mainframe computers and vacuum tubes. With the introduction of large-scale Integration circuits (LSI) and silicon chips consisting of thousands of transistors, computers reached a new level.

Microcomputers, which were physically much like the minicomputers of the third generation, however they were much cheaper enabling individuals to now use them, not just large company’s and universities. These personal computers and required an operating system that was user friendly so that people with little computer knowledge was able to use it. In 1981, IBM was releasing a 16-bit personal computer, and required a more powerful operating system then the ones available at the time, so they turned to Microsoft to deliver it. The software, called Micro Soft Disk Operating System (MS-DOS) became the standard operating system for most personal computers of that era.

In the mid-1980’s, networks of personal computers had increased a great deal, requiring a new type of operating system. The OS had to be able to manage remote and local hardware and software, file sharing and protection, among other things. Two types of systems were introduced, the network operating system in which users can copy from one station to another, and the distributed operating system, in which the computer appears to be a uni-processor system, even though it is actually running programs and storing files in a remote location. One of the best known network operating system for a distributed network is the Network File System (NFS), which was originally designed by Sun Microsystems, for use on UNIX based machines. An important feature of the NFS is its ability to support different type of computers. This allowed a machine running NFS to communicate with an IBM compatible machine running MS-DOS, which was an important addition to networking computing.

1984 saw the release of the Apple Macintosh, a low-cost workstation, which evolved from early Alto computer designs. The Macintosh provided advanced graphics and high performance for its size and cost. As the Macintosh was not compatible with other systems, it required its own operating system, which is how the Apple operating system was established. MIMIX, based on the UNIX design was also a popular choice for the Macintosh.

As computer processors got faster, operating systems also had to improve in order to take advantage of this progression. Microsoft released version 2 of MS-DOS, which adopted the many features that made UNIX so popular, although MS-DOS was designed to be smaller then, but was not as large as the UNIX operating system making it ideal for personal computers.

Modern Operating Systems

The past 9 years have seen many advances in computers and their operating systems. Processors continue to increase in speed, each requiring an operating system to handle the new developments. Microsoft Corporation has dominated the IBM compatible world, Windows being the standard operating system for majority of personal computers.

Now as computing and information technology becomes more towards the Internet and virtual computing, so too must the operating systems.

In 1992, Microsoft for Workgroups 3.1 was introduced, extending on from the previous versions. It allowed the sending of electronic mail, and provided advanced networking capabilities to be used as a client on an existing local area network. This was only the one stage in the vast evolution of the worlds most popular operating system, with the most recent being Windows NT and Windows 98, the latter being a fully Internet integrated operating system. Windows, however is not the only operating system in use today? Other’s such as UNIX, Apple Operating System and OS/Warp have also had an impact, each new version more advanced, and more user friendly then the la

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Teacher:Shaimerdenova G.S South Kazakhstan State pharmaceutical academy “Medi.

Teacher:Shaimerdenova G.S South Kazakhstan State pharmaceutical academy “Medical Biophysics, Computer Science and Mathematics” department Theme : Evolution of operating system A. Frank - P. Weisberg

Contents 1.Early Systems 2.Characteristics of Early Systems 3. Simple Batch S.

Evolution of an Operating Systems? Must adapt to hardware upgrades and new ty.

Evolution of an Operating Systems? Must adapt to hardware upgrades and new types of hardware. Examples: Character vs. graphic terminals Introduction of paging hardware Must offer new services, e.g., internet support. The need to change the OS on regular basis place requirements on it’s design: modular construction with clean interfaces. object oriented methodology. *

Evolution of Operating Systems Early Systems (1950) Simple Batch Systems (196.

Evolution of Operating Systems Early Systems (1950) Simple Batch Systems (1960) Multiprogrammed Batch Systems (1970) Time-Sharing and Real-Time Systems (1970) Personal/Desktop Computers (1980) Multiprocessor Systems (1980) Networked/Distributed Systems (1980) Web-based Systems (1990) *

Early Systems Structure Single user system. Programmer/User as operator (Open.

Early Systems Structure Single user system. Programmer/User as operator (Open Shop). Large machines run from console. Paper Tape or Punched cards. *

Example of an early computer system *

Example of an early computer system *

Simple Batch Systems Use of high-level languages, magnetic tapes. Jobs are ba.

Simple Batch Systems Use of high-level languages, magnetic tapes. Jobs are batched together by type of languages. An operator was hired to perform the repetitive tasks of loading jobs, starting the computer, and collecting the output (Operator-driven Shop). It was not feasible for users to inspect memory or patch programs directly. *

Operation of Simple Batch Systems The user submits a job (written on cards or.

Operation of Simple Batch Systems The user submits a job (written on cards or tape) to a computer operator. The computer operator place a batch of several jobs on an input device. A special program, the monitor, manages the execution of each program in the batch. Monitor utilities are loaded when needed. “Resident monitor” is always in main memory and available for execution. *

Idea of Simple Batch Systems Reduce setup time by batching similar jobs. Alte.

Idea of Simple Batch Systems Reduce setup time by batching similar jobs. Alternate execution between user program and the monitor program. Rely on available hardware to effectively alternate execution from various parts of memory. Use Automatic Job Sequencing – automatically transfer control from one job when it finishes to another one. *

Control Cards (1) Problems: 1. How does the monitor know about the nature of.

Control Cards (1) Problems: 1. How does the monitor know about the nature of the job (e.g., Fortran versus Assembly) or which program to execute? 2. How does the monitor distinguish: (a) job from job? (b) data from program? Solution: Introduce Job Control Language (JCL) and control cards. *

Special cards that tell the monitor which programs to run: $JOB $FTN $RUN $DA.

Special cards that tell the monitor which programs to run: $JOB $FTN $RUN $DATA $END Special characters distinguish control cards from data or program cards: $ in column 1 // in column 1 and 2 709 in column1 Control Cards (2) *

Job Control Language (JCL) JCL is the language that provides instructions to.

Job Control Language (JCL) JCL is the language that provides instructions to the monitor: what compiler to use what data to use Example of job format: ------->> $FTN loads the compiler and transfers control to it. $LOAD loads the object code (in place of compiler). $RUN transfers control to user program. $JOB $FTN . FORTRAN program . $LOAD $RUN . Data . $END *

Another Job/Steps example *

Another Job/Steps example *

Effects of Job Control Language (JCL) Each read instruction (in user program).

Effects of Job Control Language (JCL) Each read instruction (in user program) causes one line of input to be read. Causes (OS) input routine to be invoked: checks for not reading a JCL line. skip to the next JCL line at completion of user program. *

Resident Monitor Resident Monitor is first rudimentary OS. Resident Monitor (.

Resident Monitor Resident Monitor is first rudimentary OS. Resident Monitor (Job Sequencer): initial control is in monitor. loads next program and transfers control to it. when job completes, the control transfers back to monitor. Automatically transfers control from one job to another, no idle time between programs. *

Resident Monitor Layout *

Resident Monitor Layout *

Parts of resident monitor: Control Language Interpreter – responsible for rea.

Parts of resident monitor: Control Language Interpreter – responsible for reading and carrying out instructions on the cards. Loader – loads systems programs and applications programs into memory. Device drivers – know special characteristics and properties for each of the system’s I/O devices. Resident Monitor Parts *

Desirable Hardware Features Memory protection do not allow the memory area co.

Desirable Hardware Features Memory protection do not allow the memory area containing the monitor to be altered by a user program. Privileged instructions can be executed only by the resident monitor. A trap occurs if a program tries these instructions. Interrupts provide flexibility for relinquishing control to and regaining control from user programs. Timer interrupts prevent a job from monopolizing the system. *

Offline Operation Problem: Card Reader slow, Printer slow (compared to Tape).

Offline Operation Problem: Card Reader slow, Printer slow (compared to Tape). I/O and CPU could not overlap. Solution: Offline Operation (Satellite Computers) – speed up computation by loading jobs into memory from tapes while card reading and line printing is done off-line using smaller machines. *

Spooling (1) Problem: Card reader, Line printer and Tape drives slow (compare.

Spooling (1) Problem: Card reader, Line printer and Tape drives slow (compared to Disk). I/O and CPU could not overlap. Solution: Spooling - Overlap I/O of one job with the computation of another job (using double buffering, DMA, etc). Technique is called SPOOLing: Simultaneous Peripheral Operation On Line. *

Spooling (2) While executing one job, the OS: Reads next job from card reader.

Spooling (2) While executing one job, the OS: Reads next job from card reader into a storage area on the disk (Job pool). Outputs printout of previous job from disk to printer. Job pool – data structure that allows the OS to select which job to run next in order to increase CPU utilization. *

We assumed Uniprogramming until now I/O operations are exceedingly slow (comp.

We assumed Uniprogramming until now I/O operations are exceedingly slow (compared to instruction execution). A program containing even a very small number of I/O operations, will spend most of its time waiting for them. Hence: poor CPU usage when only one program is present in memory. *

Why Multiprogramming? Multiprogramming (also known as Multitasking) needed fo.

Why Multiprogramming? Multiprogramming (also known as Multitasking) needed for efficiency: Single user cannot keep CPU and I/O devices busy at all times. Multiprogramming organizes jobs (code and data) so CPU always has one to execute. A subset of total jobs in system is kept in memory. One job selected and run via job scheduling. When it has to wait (for I/O for example), OS switches to another job. *

Requirements for Multiprogramming Hardware support: I/O interrupts and DMA co.

Requirements for Multiprogramming Hardware support: I/O interrupts and DMA controllers in order to execute instructions while I/O device is busy. Timer interrupts for CPU to gain control. Memory management several ready-to-run jobs must be kept in memory. Memory protection (data and programs). Software support from the OS: For scheduling (which program is to be run next). To manage resource contention. *

References 1.Sameer, Shaikh. Complete Computer Hardware Only. PediaPress. pp.

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Plan: 1. Software. Types of the software, purpose and characteristic. Basic concepts of OS. 2. Evolution of operating systems. Classification of operating systems, including for mobile devices. Classification of desktop applications.

1. Computer Software What we’ll cover for this lecture topic: Software categories Applications software Systems software What is an operating system? What does it do for me? What does it do for application programs? What is a translator?

Application software Application software It is the reason that one wants to buy a computer: • printout out paychecks • play Mortal Kombat • keep track of a stamp collection • do your taxes • generate a fancy newsletter • guide robots • keep a budget • draw a flowchart • browse the Web • design a car

Includes many executable files and data files: Includes many executable files and data files: Installer program (eg: setup.exe) Uninstaller program (why important?) Main executable file (eg: winword.exe) Support modules (eg: .dll files) Called by the PROGRAM, not by the user Data modules (eg: MS Word dictionary)

I. The Operating System A type of system software that underlies all other software. It manages all software and hardware tasks. It provides a common set of computer functions such as input from a keyboard and output to a monitor. It provides the user interface……that is: How can something as simple-minded as a processor and memory present you with something as rich as the Mac or Windows GUI?

EXAMPLES of I/O operations EXAMPLES of I/O operations OS reads mouse movement and writes to display screen. You move the mouse---what do you expect to happen? What that involves… Manage interrupt. OS reads mouse wheels. OS draws cursor arrow (changes pixel colors so arrow appears to be “moving”).

OS identifies selected objects on the desktop OS identifies selected objects on the desktop You select an icon--what do you expect to see? What that involves…! FIRST: you move the cursor to point to icon… Draws “moving cursor…” OS keeps table of icon placements… Looks at current cursor placement and compares it to that table. NEXT: you single-click mouse button to SELECT it: What do you expect to see? OS does all this!

OS does system control options from Start button: OS does system control options from Start button: Shut down; Restart.

OS does universal ops from the View menu: OS does universal ops from the View menu: Show/Hide Toolbars & Status bar; Large icons, Small icons; List; Details; Arrange Icons etc.

>1 program or person can share computer resources. >1 program or person can share computer resources. CPU is idle ~90% of time, waiting for user input ! Multiprogramming Run two or more programs concurrently. eg: Calculate payroll and Accts payable and WP and … 1. Multi-user OS (eg: Unix).

2. Single-user OS (eg, Windows) 2. Single-user OS (eg, Windows) Referred to as multitasking, which is multiprogramming for single-user OS. One active app; others run in the background

II. Translators (revisited!) How do people write programs? Only language a computer understands? A translator (or compiler): Program that converts high-level source code into low-level machine language (object code)-- can then be processed directly by the computer’s binary circuits. Running a source program is a two-step process: Execute the translator program first: converts ASCII source into executable machine language creates a new file containing the object code. Execute that NEW object code file.

What is an Operating System (2)? An Operating System is a program that acts as an intermediary/interface between a user of a computer and the computer hardware. OS goals: Control/execute user/application programs. Make the computer system convenient to use. Ease the solving of user problems. Use the computer hardware in an efficient manner.

Services provided by an OS Facilities for program creation editors, compilers, linkers, debuggers, etc. Program execution loading in memory, I/O and file initialization. Access to I/O and files deals with the specifics of I/O and file formats. System access resolves conflicts for resource contention. protection in access to resources and data.

Why are Operating Systems Important? Important to understand and know how to correctly use when writing user applications. Large and complex systems that have a high economic impact and result in interesting problems of management. Few actually involved in OS design and implementation but nevertheless many general techniques to be learned and applied. Combines concepts from many other areas of Computer Science: Architecture, Languages, Data Structures, Algorithms, etc.

Evolution of Operating Systems The evolution of operating systems is directly dependent to the development of computer systems and how users use them. Here is a quick tour of computing systems through the past fifty years in the timeline.

Early Evolution 1945: ENIAC, Moore School of Engineering, University of Pennsylvania. 1949: EDSAC and EDVAC 1949 BINAC - a successor to the ENIAC 1951: UNIVAC by Remington 1952: IBM 701 1956: The interrupt 1954-1957: FORTRAN was developed

Operating Systems by the late 1950s By the late 1950s Operating systems were well improved and started supporting following usages : It was able to Single stream batch processing It could use Common, standardized, input/output routines for device access Program transition capabilities to reduce the overhead of starting a new job was added Error recovery to clean up after a job terminated abnormally was added. Job control languages that allowed users to specify the job definition and resource requirements were made possible.

Operating Systems In 1960s 1961: The dawn of minicomputers 1962 Compatible Time-Sharing System (CTSS) from MIT 1963 Burroughs Master Control Program (MCP) for the B5000 system 1964: IBM System/360 1960s: Disks become mainstream 1966: Minicomputers get cheaper, more powerful, and really useful 1967-1968: The mouse 1964 and onward: Multics 1969: The UNIX Time-Sharing System from Bell Telephone Laboratories

Supported OS Features by 1970s Multi User and Multi tasking was introduced. Dynamic address translation hardware and Virtual machines came into picture. Modular architectures came into existence. Personal, interactive systems came into existence.

Control questions What is Software? Differentiate System software and Application software. What are the responsibilities of Operating Systems? Define the following with suitable examples. Single–user OS Multi-user OS What are utility programs? Define some tasks performed by them. What is meant by library programs? What are program language translators? Briefly describe three translating approaches. State the advantages and disadvantages of Bespoke Application Software.

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