Operating System

  • An operating system is a program which manages all the computer hardware’s.
  • It provides the base for application program and acts as an intermediary between a user and the computer hardware.
  • The operating system has two objectives such as:
    • Firstly, an operating system controls the computer’s
    • The second objective is to provide an interactive interface to the user and interpret commands so that it can communicate with the hardware.
  • The operating system is very important part of almost every computer system.

Managing Hardware

  • The prime objective of operating system is to manage & control the various hardware resources of a computer
  • These hardware resources include processer, memory, and disk space and so on.
  • The output result was display in In addition to communicating with the hardware the operating system provides on error handling procedure and display an error notification.
  • If a device not functioning properly, the operating system cannot be communicate with the device.

System goals

  •  The purpose of an operating system is to be provided an environment in which an user can execute programs.
  • Its primary goals are to make the computer system convenience for the user.
  • Its secondary goals are to use the computer hardware in efficient manner.

History and Evaluation Of Operating System

The evolution of operating systems is directly dependent on 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
  • 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 - Late 1950s

  • By the late 1950s Operating systems were well improved and started supporting following usages:
  • It was able to perform Single stream batch
  • It could use Common, standardized, input/output routines for device
  • Program transition capabilities to reduce the overhead of starting a new job were
  • Error recovery to clean up after a job terminated abnormally was
  • 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 became mainstream
  • 1966: Minicomputers got cheaper, more powerful, and really
  • 1967-1968: Mouse was
  • 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
  • Dynamic address translation hardware and Virtual machines came into
  • Modular architectures came into
  • Personal, interactive systems came into existence.

Accomplishments after 1970

  • 1971: Intel announces the microprocessor
  • 1972: IBM comes out with VM: the Virtual Machine Operating System
  • 1973: UNIX 4th Edition is published
  • 1973: Ethernet
  • 1974 The Personal Computer Age begins
  • 1974: Gates and Allen wrote BASIC for the Altair
  • 1976: Apple II
  • August 12, 1981: IBM introduces the IBM PC
  • 1983 Microsoft begins work on MS-Windows
  • 1984 Apple Macintosh comes out
  • 1990 Microsoft Windows 0 comes out
  • 1991 GNU/Linux
  • 1992 The first Windows virus comes out
  • 1993 Windows NT
  • 2007: iOS
  • 2008: Android OS

Generation of Operating System

Operating Systems have evolved over the years. So, their evolution through the years can be mapped using generations of operating systems. There are four generations of operating systems.

These can be described as follows

1. First Generation ( 1945 - 1955 ): Vacuum Tubes and Plugboards

Digital computers were not constructed until the second world war. Calculating engines with mechanical relays were built at that time. However, the mechanical relays were very slow and were later replaced with vacuum tubes. These machines were enormous but were still very slow.

These early computers were designed, built and maintained by a single group of people. Programming languages were unknown and there were no operating systems so all the programming was done in machine language. All the problems were simple numerical calculations.

By the 1950’s punch cards were introduced and this improved the computer system. Instead of using plugboards, programs were written on cards and read into the system.

2. Second Generation ( 1955 - 1965 ): Transistors and Batch Systems

Transistors led to the development of the computer systems that could be manufactured and sold to paying customers. These machines were known as mainframes and were locked in air-conditioned computer rooms with staff to operate them.

The Batch System was introduced to reduce the wasted time in the computer. A tray full of jobs was collected in the input room and read into the magnetic tape. After that, the tape was rewound and mounted on a tape drive. Then the batch operating system was loaded in which read the first job from the tape and ran it. The output was written on the second tape. After the whole batch was done, the input and output tapes were removed and the output tape was printed.

3. Third Generation ( 1965 - 1980 ): Integrated Circuits and Multiprogramming

Until the 1960’s, there were two types of computer systems i.e the scientific and the commercial computers. These were combined by IBM in the System/360. This used integrated circuits and provided a major price and performance advantage over the second generation systems.

The third generation operating systems also introduced multiprogramming. This meant that the processor was not idle while a job was completing its I/O operation. Another job was scheduled on the processor so that its time would not be wasted.

4. Fourth Generation ( 1980 - Present ): Personal Computers

Personal Computers were easy to create with the development of large-scale integrated circuits. These were chips containing thousands of transistors on a square centimeter of silicon. Because of these, microcomputers were much cheaper than minicomputers and that made it possible for a single individual to own one of them.

The advent of personal computers also led to the growth of networks. This created network operating systems and distributed operating systems. The users were aware of a network while using a network operating system and could log in to remote machines and copy files from one machine to another.