Ethical Hacking

They dedicate their skills to serve their clients. Instead of spending long nights inside obscure rooms filled with computers looking for some victim, they work inside corporations, finding ways to protect the networks and computer systems.

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OPERATING SYSTEM:-

            An operating system is the interface between the user and the

architecture.

          EXAMPLES:-WINDOWS XP,WINDOWS 7,WINDOWS 8,WINDOWS VISTA

                    LINUX,UNIX,MAC ETC.

 

LINUX:-

        The Nineties started with Linus Torvalds, a Swedish speaking Finnish student,

buying a 386 computer and writing a brand new POSIX compliant kernel. He put

the source code online, thinking it would never support anything but 386 hardware.

Many people embraced the combination of this kernel with the GNU tools, and the

rest, as they say, is history.

Today more than 90 percent of supercomputers (including the complete top 10), more

than half of all smartphones, many millions of desktop computers, around 70 percent

of all web servers, a large chunk of tablet computers, and several appliances (dvdplayers,

washing machines, dsl modems, routers, ...) run Linux. It is by far the most

commonly used operating system in the world.

      

DISTIBUTIONS:-

             A Linux distribution is a collection of (usually open source) software on top of a

Linux kernel. A distribution (or short, distro) can bundle server software, system

management tools, documentation and many desktop applications in a central secure

software repository. A distro aims to provide a common look and feel, secure and

easy software management and often a specific operational purpose.

Red Hat:-

        Red Hat is a billion dollar commercial Linux company that puts a lot of effort in

developing Linux. They have hundreds of Linux specialists and are known for their

excellent support. They give their products (Red Hat Enterprise Linux and Fedora)

away for free. While Red Hat Enterprise Linux (RHEL) is well tested before release

and supported for up to seven years after release, Fedora is a distro with faster updates

but without support.

OPEN SOURCE:-

           of or relating to or being computer software for which the source code is freely availabl

KERNEL:-

        A kernel is the core of an operating system. The operating system is all of the programs that manages the hardware and allows users to run applications on a computer. The kernel controls the hardware and applications. Applications do not communicate with the hardware directly, instead they go to the kernel. In summary, software runs on the kernel and the kernel operates the hardware.

 Without a kernel, a computer is a useless objec

http://thelinuxdesk.com/2012/09/07/operating-system-kernel-types/