An Operating System (OS) is an interface between hardware and user which is responsible for the management and coordination of activities and the sharing of the resources of the computer that acts as a host for computing applications run on the machine. As a host, one of the purposes of an operating system is to handle the details of the operation of the hardware. This relieves application programs from having to manage these details and makes it easier to write applications.

logo-big-789555 Almost all computers (including handheld computers, desktop computers,supercomputers, video game consoles) as well as some robots, domestic appliances (dishwashers, washing machines), and portable media players use an operating system of some type.


Some of the oldest models may, however, use an embedded operating system that may be contained on a compact disk data storage device.In August 2009 , Unix celebrates the 40th anniversary of the Unix operating system.Unix was not the first operation system on any platform , Unix transitioned from the mini-computer era into the micro-computer era and the personal computer era , winning fans as it went forward .Now  , lets take a look at the biggest desktop operating systems milestones of the past 40 years.


Unix was brought to the life on a spare DEC PDP-7 at AT&T Bell Lab.When AT&T decided to abandon the Multics(Multiplexed Information and Computing Service ) operating system on its mini-computers . Ken Thomson and Dennis Ritchie cobbled together an operating system so they could continue to play a space travel game that Thomson had developed.A colleague named it UNICS , the Uniplexed Information and Computing Service , which changed into UNIX.


Intergalactic digital research’s maverick brain Gray Kildall creates CP/M, a simple microcomputer operating system for simple microcomputers. It would be the model for command –line DOS variations for two decades.


The godfather of Open Source is born when the Computer Systems Research Groups at UC Berkeley Software Distribution. BSD will ultimately spawn alternatives to some commercial microcomputer operating systems- and form the core of at least one major commercial operating system, Mac OS X.

Tandy/Radio Shack introduces a line of affordable home computer and debuts a family–friends operating system called TRS-DOS with such related-M-for-Mature commands as kill. Other companies’ versions of DOS substitute the less menacing DEL command for Delete.


Apple DOS 3.1 debuts, it will run the Apple II series for computers for the next five years.


The IBM PC is born and so are PC-DOS and its alter ego, MSDOS.msdos-logo


Free Software Advocate Richard Stallman announces the plan for GNU a Unix-like operating system that contains no proprietary software. Twenty-six years later, GNU’s official kernel, GNU Hurd, will still be incomplete.


During the Super Bowl, Apple airs a commercial in which a females athlete throws a huge screen displaying a through a huge screen display a stern , Big Brother –like visage .In the ensuing chaos ,people forget that there are more than two computing platforms and concentrate on the epic battle between DOS and the Macintosh.


Microsoft Windows 1.01 retails, at a list price of 99 dollars. Its market as a graphical user interface that extends the Dos operating system and lets users run several programs at the same time and freely switch among tem. But it’s not touted as an actual operating system until a decade later.


The Atari ST appears, running a color graphical user interface: GEM from digital Research, the people who brought us CP/M, like Windows< GEM runs on top of a less attractive, command-Line-drive operating system. It becomes a popular graphics and digital music platform, which gives Apples a few ideas to explore later.

A few month later , the Amiga appears .Its operating system is built on a kernel that handles preemptive multitasking , so it start with an advantage . The OS also contains a disk operating system, an APL layer called Intuition, and a graphical user interface called workbench. People can choose at will between a command line and the workbench graphical interface and seem pretty happy about it. It becomes a popular video platform which gives Apples a few ideas to explore later.


GEOS appears, and gives Apple and Microsoft a few ideas to explore later.


OS/2 first makes news when Microsoft announces its operating system/2 , MS OS/2 , develop to harness the power of Intel’s 80286 and 80386 microprocessors . As IBM and Microsoft’s joint operating agreement falls apart OS/2 becomes an IBM product , and Microsoft gives its graphical operating system a different name – Windows NT . Years of confusion ensue as people try to figure out which Windows is actually Windows.


IBM OS/2 1.1 appears in November, with a graphical user interface and no real acknowledgment that one of its parents is Microsoft.


Four years after being ” encouraged ” to leave Apple and founding next inc .Steve jobs takes his career to the next level with the release of next step . The new operating system builds a beautiful graphical layer on top of BSD adds an object-oriented development tool kit n and secures jobs, eventual return to Apple . He holds onto that capital X in NeXT so he can slap it on apple’s next operating system.


Windows 3.0 becomes the first Microsoft windows with a shot at a mainstream audience, but it’s still just a DOS – based operating system.

005.MS Windows v3.1 Over the next few years , Microsoft introduces Windows 3.1 a bug-fix and enhancement release that meets with widespread approval , and the Windows for Workgroups 3.1 and 3.11 extensions, which add and improve native networking support . But it’s still not a real OS.


Norse OS god linus Torvalds releases an open-source, kernel tat sort of bears his name Linux is officially pronounced ” leen-ooks ” to reflect its Finnish origins .

images (7) The Linux kernel will subsequently be combined with GNU software to create an array of open – source operating system known as Linux distributions.


Windows NT appears .and everyone assumes the NT stands for new technology. Microsoft later denies this.ntlogo But it can’t deny that NT is the love child of its union with IBM and HALF brother to OS/2.


Windows 95 appears to great fanfare. it spawns a new line of Microsoft operating systems with one foot in the 32-fit world and another stuck in the mud with not-yet-obsolete 16-bits software . who’d have thunk it that it would take six years to waves goodbye to all that? but windows 98 , 1999′s 98 second edition and 2000′s windows me had to pass before windows could move on.09MS_95

To slightly less fan tare. BeOS arrives for the power Pc platform. it carries high hopes of taking the digital media world by storm and replacing Mac OS classic . eventually , takes with Apple Flounder , and BeOS losses out to open step as the foundation got the new Mac OS.


The arrival of Macintosh System 7.6 heralds a new name – Mac OS- and a new game called waiting for Copland. In the end we abandon the wait for.

mac_os_logo Copland when Apple buys NeXT and adapts its operating system instead.


Apple abandons its old Os core and introduces Mac OS X. The X is a Roman numeral for 10, but some think it’s a nod to x windows (which is in there) and the NeXT operating system ( which is also in there) , Either way , X marks the spot where apple moved away from 1984 and into a brave new world .mac

The windows XP family is born. IT begins with Windows XP. And Increase every two years with a new – but not necessarily a full – release.


XP service pack –1



XP service pack -2


Windows vista windows-vista-logo


Vista service pack 1 and XP service pack 3 .


In 2009 , Microsoft introduce their new Operating System named as “Windows 7 “.First , they launch the Beta version of Windows 7 and then Release Candidate version in May , and now Release TO Manufacture version.windows_7_official_logo

Its final version will be available in the market from the  last of October.

[Sources] Spider , Computerworld and Wikipedia