Evolution of Operating Systems

  • In the early computers there were no Operating Systems.
  • By in the early 1960s, when the commercial computer services and commercial computer merchants started supplying the extensive apparatus for reformation of the development, execution of jobs, and scheduling on batch processing systems.
  • With the advancement of the commercial computer services we have come across a number of Operating Systems software.
  • Starting from the DOS, a lot much Operating Systems software has got developed through out the ages like the UNIX, Oracle etc depending on the requirement.
  • The most commonly-used Operating Systems for laptops and modern Desktops Operating Systems were the Microsoft Windows.
  • Tough more powerful servers make the use of FreeBSD, Linux, and other Unix-like systems a lot.
  • Though, these types of Operating Systems, particularly Mac OS X, are also installed on the personal computers.

Types of Operating Systems Software:

  1. Operating Systems for Single User Systems: Single User Systems provides a base for only single user at a particular time. These types of Operating Systems software are more popularly with Desk Tops.
  2. Operating Systems for Multi User Systems: Multi User Systems provide a regulated admittance for a certain number of users by keeping up a database of identified users.

Microsoft Contributions

  • Microsoft has designed and marketed the Windows Operating Systems as a collection of several Operating Systems.
  • Microsoft was the first to introduce the idea of an operating setting which was named as Windows in November 1985 as an attachment to the MS-DOS in reply to the increasing curiosity in Graphical User Interfaces (GUIs).
  • Microsoft Windows in the end started to govern the world market of the personal computers, going far ahead of Mac OS, which was predominating before its era.
  • The latest version of Windows present in the market is Windows Vista while the latest server version of it is the Windows Server 2003.
  • The descendant to Windows Server 2003 will be the Windows Server 2008 which is still in beta version and is at present being under tested.


Memory Management

  • Present computer structural designs assemble the computer's memory in a hierarchical process, beginning from the highest registers, random access memory, CPU cache, and disk storage.
  • A computer Operating Systems memory manager synchronizes the utility of these numerous kinds of memory by tracking which one is obtainable, which is to be assigned or de-assigned and how to progress data between them.
  • Generally the activity is termed as virtual memory management as it amplifies the amount of memory obtainable for each process by creating the disk storage seems like main memory.
  • There is a pace penalty connected with utilizing disks or other slower storage as memory.
  • This memory management also is administers the virtual addresses.
  • The procedure is known as "paging" or "swapping" and the terminology varies between different Operating Systems.

Process Management

  • Each and every program running on a computer whether it a service or an application, is generally a process.
  • Most Operating Systems facilitate simultaneous execution of many processes and programs at once through multitasking, even with one CPU.
  • The most elementary of computers multitasking is done by simply switching processes rapidly.
  • Most Operating Systems permit a process to be allocated a priority which affects its distribution of CPU time.

Disk and File Systems

  • Generally, computer Operating Systems also includes support for file systems.
  • Modern file systems include a hierarchy of directories.
  • While the idea is theoretically alike transversely all general-purpose file systems, some differences in implementation survive.


Two obvious examples of Evolution of Operating Systems are: case sensitivity and character utilized to separate directories.


  • Computer Operating Systems also comprise some standards of security.
  • Security is based on the two concepts.
  • The Operating Systems offers admission to a number of resources, directly or indirectly, like files on a local disk, personal information about users, privileged system calls, and the services presented by the programs running on the system.
  • The Operating Systems is competent of unique between some requesters of these resources who are authorized to access the resource and others who are forbidden.
  • Internal security is regarded as an already running program.
  • On some systems, a program once it is running has no limitations, but frequently the program has an individuality which it keeps and is used to check all of its requests for resources.
  • To launch identity there may be a process of authentication.
  • Often a username must be cited and each username must possess a password.
  • Other procedures of authentication are magnetic cards or biometric data, may be utilized instead.
  • In some cases, especially connections from the network, resources may be admittance with no confirmation at all.

Types of Computer Operating Systems:

UNIX Operating Systems

  • It is a modified KDE desktop operating under Linux.
  • The Unix-like family is a miscellaneous group of Unix Operating Systems, with several major sb-categories including BSD, System V, and Linux.
  • UNIX systems run on a wide variety of machine structural designs.
  • They are utilized heavily as server systems in business, as well as workstations in educational and engineering environments.
  • Complementary software UNIX options are Linux and BSD, are famous in these areas.

Microsoft Windows Operating Systems

  • The Microsoft Windows family of Operating Systems derived as append to the older MS-DOS milieu for the IBM PC.
  • Contemporary versions are based on the newer Windows NT core that was initially intended for OS/2 and borrowed from VMS. Windows runs on x86, x86-64 and Itanium processors.
  • Previous versions also operate on the MIPS, DEC Alpha, Fairchild Clipper and PowerPC structural designs.

Sun Solar Operating Systems

  • One of the world's largest on-hand inventories of fully tested, renovated Sun Microsystems paraphernalia.
  • Solar Systems Peripherals, Inc. is devoted to providing user with outstanding values in Sun Microsystems.