Monday, 3 February 2020

Introduction to Operating Systems

What is an Operating System?

  • Operating system is a system software which is required in order to run application programs and utilities. It perform interaction between application programs and all the hardware of the computer. 
  • Examples of operating system are UNIX, MS-DOS, Windows-NT/2000, OS/2, MS-Windows - 98/XP/Vista, android and Mac OS etc.
www.oscspoint.blogspot.com
Different-2 Operating Systems

  • A computer system has many resources (hardware and software), which are required r to complete different-2 task. 
  • Input / output equipment, memory, file storage space, CPU etc. are the most frequently needed resources. 
  • The operating system serves as manager of the above-mentioned resources and assigns them to specific programs and users whenever appropriate to perform a specific function. 
  • Operating system work as resource manager i.e. it can manage the resource of a computer system internally or externally. The resources are processor, memory, files, and I/O devices. 
  • In simple terms, an operating system work as interface between the user and the hardware/machine.
  • An operating system or OS is a software program that allows the computer hardware to communicate with computer software and work with it. 
  • One computer and software programs would be useless without a computer operating system. The picture shows Microsoft's original packaging for Windows XP.
  • When computers were first introduced, the user used a command line interface to interact with them, which required commands. 
  • But today, almost every computer uses an operating system with a GUI (Graphical User Interface), which is much easier to use and operate.

Examples of Computer Systems

  • Microsoft Windows 10 - PC and IBM compatible operating system. Microsoft Windows is the most common and used operating system.
  • Apple macOS - Apple Mac operating system. Today, the only Apple computer operating system is macOS.
  • iOS - Operating system used with the Apple iPhone and iPads.
  • Chromium - Google operating system used with Chromebooks.
  • Oxygen OS - OnePlus' proprietary operating system.
  • Ubuntu Linux - A popular variant of Linux used with PC and IBM compatible computers.
  • Google Android - Operating system used with Android compatible phones and tablets.

Two views on Operating System


  1. User's View
  2. System View
User View 
  • These systems are designed to monopolize one user's energy, in order to maximize the work the user does. In these cases, the operating system is designed primarily for ease of use, with some attention being paid to performance, and none being paid to use of resources.
System View 
  • A computer system is made up of many resources such as-hardware and software-that have to be handled efficiently. The operating system serves as resource manager, determines between competing demands, manages program execution etc.

Operating System Management Tasks

  • Processor Management which involves putting the tasks into order and pairing them into manageable size before they go to the CPU.
  • Memory Management which coordinates data to and from RAM (random-access memory) and determines the necessity for virtual memory.
  • Device Management which provides interface between connected devices.
  • Storage Management which directs permanent data storage.
  • Application Management which allows standard communication between software and your computer.
  • User interface which allows you to communicate with your computer.

Wednesday, 7 February 2018

Evolution of Operating Systems

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.

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 3.0 comes out
  • 1991 GNU/Linux
  • 1992 The first Windows virus comes out
  • 1993 Windows NT
  • 2007: iOS
  • 2008: Android OS

And as the research and development work still goes on, with new operating systems being developed and existing ones getting improved and modified to enhance the overall user experience, making operating systems fast and efficient like never before.