OS V/S Kernels

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OPERATING SYSTEMS:  There is no completely adequate definition of an Operating System. OS exist because they offer reasonable way to solve the problem of creating a usable Computing System and covers many roles and functions :
  • It is a system program that manages a computer's hardware.
  • It provides a basis for application programs and act as an intermediate between the computer users and computer hardware.
  • provides GUI,Shell,tools for you to interact with the hardware, provide a framework which can be leveraged to write application softwares which can run over the OS.










  • OS as a resource allocator:
    1. Manages all resources
    2. Decides between conflicting requests for efficient and fair resource use.
    • OS is a control program:

    1. Controls execution of programs to prevent errors and improperuse of the computer.

    Examples of OS:
    Windows (XP, 7, 8, etc...),Ubuntu, Kubuntu, Mac OSX, Solaris, etc.


    KERNALS:(Types:Monolithi,Micro,Hybrid):
    The kernel is part of the operating system which manages the system resources and interacts directly with the hardware and provides low level services like:

    · device driver
    · network management

    · process management
    · memory management
    · system calls
    · Interrupt handling

    BASIC DIFFERNCE
     Kernel as described above is the heart of OS which
    manages the core features of an OS while if some
    useful applications and utilities are added over the kernel,then the complete package becomes an OS. So, it can easily be said that an operating system consists of a 
    kernel space and a user space.
    So, we can say that Linux is a kernel as it does not 
    include applications like file-system utilities, windowing systems and graphical desktops, system administrator commands, text editors, compilers etc. So, various companies add these kind of applications over linux kernel and provide their operating system like  ubuntu, suse, centOS, redHat etc.

    System softwares(compiler,assembler,debugger) are associated with OS and runs in background and necessarily not a part of the kernal and the application softwares(spreadsheets,games,MS-office) which include several programs not associated with the OS.The kernel is the software that directly manages your hardware, allowing application libraries and software like GNOME and Firefox to run on many types of hardware without much difficulty. 



    Kernals used :
    •  WINDOWS uses hybrid kernels ie NT(Networking Technology).
    •  Ubuntu is an OS uses LINUX as its kernel.Similarly, Fedora, Debian, Mageia are UNIX-like OS build on LINUX kernel.
    • iOS uses XNU kernels.
    • Android is also bulid on LINUX kernel.

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