What exactly is an operating system?
The most important program that runs on a computer.
Operating systems perform basic tasks, such as recognizing input from the keyboard, sending output to the display screen, keeping track of files and directories on the disk, and controlling peripheral devices such as disk drives and printers.
Operating systems can be classified as follows:
- multi-user : Allows two or more users to run programs at the same time. Some operating systems permit hundreds or even thousands of concurrent users.
- multiprocessing : Supports running a program on more than one CPU.
- multitasking : Allows more than one program to run concurrently.
- multithreading : Allows different parts of a single program to run concurrently.
- real time: Responds to input instantly. General-purpose operating systems, such as DOS and UNIX, are not real-time.
Operating systems provide a software platform on top of which other programs, called application programs, can run. The application programs must be written to run on top of a particular operating system.
Unix
Pronounced yoo-niks, a popular multi-user, multitasking operating system developed at Bell Labs in the early 1970s.
History
Since it began to escape from AT&T's Bell Laboratories in the early 1970's, the success of the UNIX operating system has led to many different versions: recipients of the (at that time free) UNIX system code all began developing their own different versions in their own, different, ways for use and sale. By the late 1970's, a ripple effect had come into play. In the early 1980's, the market for UNIX systems had grown enough to be noticed by industry analysts and researchers. Throughout the early and mid-1980's, the debate about the strengths and weaknesses of UNIX systems raged, often fuelled by the utterances of the vendors themselves who sought to protect their profitable proprietary system sales by talking UNIX systems down. In 1984, another factor brought added attention to UNIX systems. Although UNIX was still owned by AT&T, the company did little commercially with it until the mid-1980's. In a move intended to unify the market in 1987, AT&T announced a pact with Sun Microsystems, the leading proponent of the Berkeley derived strain of UNIX. XPG 4 was released in October 1992. In early 1993, AT&T sold it UNIX System Laboratories to Novell which was looking for a heavyweight operating system to link to its NetWare product range. In 1995 X/Open introduced the UNIX 95 brand for computer systems guaranteed to meet the Single UNIX Specification.
Invention and Development
Originally developed in 1969 by a group of AT&T employees at Bell Labs, including Ken Thompson, Dennis Ritchie, Brian Kernighan, Douglas McIlroy, and Joe Ossanna. The Unix operating system was first developed in assembly language, but by 1973 had been almost entirely recoded in C, greatly facilitating its further development and porting to other hardware. Today's Unix system evolution is split into various branches, developed over time by AT&T as well as various commercial vendors, universities (such as University of California, Berkeley's BSD), and non-profit organizations.
Versions Available
| Linux | BSDI | IBM's OS/390 | WindowsNT | Digital UNIX | Hewlett Packard HP-UX | IBM AIX | SCO UnixWare | SGI IRIX | Sun Solaris |
Uses
Due to its portability, flexibility, and power, UNIX has become a leading operating system for workstations. Historically, it has been less popular in the personal computer market.
Future
The continued lack of complete portability across competing versions of Unix, as well as the cost advantage of Linux and Windows on x86 commodity processors, will prompt IT organizations to migrate away from Unix, suggests a recent poll by Gartner Group.
Why Use It?
Unix enabled a number of startup companies to succeed by giving them a low-cost platform to build on. It was a core building block for the Internet and is at the heart of telecommunications systems today. It spawned a number of important architectural ideas such as pipelining, and the Unix derivative Mach contributed enormously to scientific, distributed and multiprocessor computing.
Linux
Pronounced lee-nucks or lih-nucks. A freely-distributable open source operating system that runs on a number of hardware platforms.
Linux is, in simplest terms, an operating system. It is the software on a computer that enables applications and the computer operator to access the devices on the computer to perform desired functions.
History, Invention and Development
In June 1971, Richard Matthew Stallman joined MIT Artificial Intelligence Laboratory as a programmer where he gained popularity with the hacker community and came to be known by his now popular name RMS. In 1989, Stallman released the first program independent GNU General Public Licence now popularly known as GPL or copyleft. n 1990, A finnish student by name Linus Torvalds studying in the University of Helsinki came into contact with Andy Tanenbaum's OS, Minix.After 1997, a programming model other than the GPLed model emerged which is now popularly known as the Open Source Initiative. Linus wanted to upgrade Minix by putting in more features and improvements. But he was prohibited by Tanenbaum to do so. Then Linus decided to write his own kernel and released it under GPL. This kernel is now popularly known as Linux.
Versions Available
| Debian | Ubuntu | Fedora | OpenSUSE | Mandriva | Slackware | FreeBSD | Mint | PCLinuxOS |
Uses
One of the most noted properties of Linux is where it can be used. Linux, which began its existence as a server OS and Has become useful as a desktop OS, can also be used on all of these devices.
Future
Linux is the OS of choice because “it's free, it's fast and it's secure.” And since error messages can generally be followed to a solution, there’s a do-it-yourself aspect to Linux that’s especially appealing.
Why Use It?
Because it's free, and because it runs on many platforms, including PCs and Macintoshes, Linux has become an extremely popular alternative to proprietary operating systems.
Mac OSX
(Pronounced Mac Oh-Ess Ten) The latest operating system for Apple's Macintosh computers.
History
1985: Forced out of the company he co-founded, Steve Jobs launches NeXT, a hardware and software company, partially funded by future presidential candidate, Ross Perot. December 1996: Apple buys NeXT for \\$429 million.March 1999: Apple releases OS X Server 1.0: the first major fruit of the company’s OpenStep acquisition. September 2000: It’s a bear! Apple releases a public beta of OS X, codenamed Kodiak.March 2001: The first of the big cat operating systems enters the wild with Cheetah. September 2001: Six months after the release of Cheetah, Apple releases 10.2, Jaguar. May 2002: Jobs takes the stage alongside a coffin at Apple’s annual World Wide Developer Conference — a less than subtle way of announcing the death of OS 9. August 2002: Version 10.3 Panther, announced at the aforementioned WWDC, hits the streets. August 2005: OS X 10.4 Tiger is released. August 2008: OS X 10.6 Snow Leopard is released, becoming the first version of OS X to drop support for older PowerPC systems. In Summer 2011, Lion was released.
Invention and Development
Mac OS X is the newest of Apple Inc.'s Mac OS line of operating systems. Although it is officially designated as simply "version 10" of the Mac OS, "version 9" had a completely different codebase, file system, design, and hardware support. Mac OS had been Apple's primary operating system since 1984, and the family was backward compatible, so Mac OS X supported an emulated version 9 until version 10.5. Apple expected that developers would port their software to the considerably more powerful OPENSTEP libraries once they learned of its power and flexibility. Instead, several major developers such as Adobe told Apple that this would never occur, and that they would rather leave the platform entirely. This "rejection" of Apple's plan was largely the result of a string of previous broken promises from Apple; after watching one "next OS" after another disappear and Apple's market share dwindle, developers were not interested in doing much work on the platform at all, let alone a re-write.Versions Available
| v10.0 "Cheetah" | v10.1 "Puma" | v10.2 "Jaguar" | v10.3 "Panther" | v10.4 "Tiger" | v10.5 "Leopard" | v10.6 "Snow Leopard" | v10.7 "Lion" |
Uses
Mac OS X introduced a number of new capabilities to provide a more stable and reliable platform than its predecessor, Mac OS 9. For example, pre-emptive multitasking and memory protection improved the system's ability to run multiple applications simultaneously without them interrupting or corrupting each other. Mac OS X architecture implements a layered design. The layered frameworks aid rapid development of applications by providing existing code for common tasks.
Future
When Steve Jobs first introduced Lion, he set a bold goal: to take what has made the iPad and the iPhone so successful and bring it to the desktop. Apple isn’t allowing touch and PC user interfaces to coexist in the same OS; rather, they’re moving the PC user interface toward a touch interface. Merging iOS and Mac OS fits this vision perfectly. Apple doesn’t want users to think about which device—touch or Mac—they should use for a certain task; they want them to be able to pick it up and just do it. That’s a grand vision for computing.
Why Use It?
This is ultimately a simple yet tough question to answer, and the best way of looking at OS X Server is not that it solves some unknown problem, but rather that it provides new and enhanced functionality that may be useful to you, depending on your needs. One of the major differences between the previous versions of Mac OS and OS X was the addition of the Aqua GUI, a graphical user interface with water-like elements. Apple has continued to change aspects of the OS X appearance and design, particularly with tweaks to the appearance of windows and the menu bar. pple also made changes to applications: they resume in the same state as they were before they were closed (similar to iOS). Documents auto-save by default.
Windows
A family of operating systems for personal computers. Windows dominates the personal computer world, running, by some estimates, on 90% of all personal computers.
History
The first version of Microsoft Windows, version 1.0, released in November 1985, lacked a degree of functionality, achieved little popularity and was to compete with Apple's own operating system. Microsoft Windows version 3.0, released in 1990, was the first Microsoft Windows version to achieve broad commercial success, selling 2 million copies in the first six months. In July 1993, Microsoft released Windows NT based on a new kernel. Windows NT 3.1 was the first release of Windows NT. On August 24, 1995, Microsoft released Windows 95, a new, and major, consumer version that made further changes to the user interface, and also used preemptive multitasking. Next in the consumer line was Microsoft Windows 98 released on June 25, 1998. As part of its "professional" line, Microsoft released Windows 2000 in February 2000. In October 2001, Microsoft released Windows XP, a version built on the Windows NT kernel that also retained the consumer-oriented usability of Windows 95 and its successors. In April 2003, Windows Server 2003 was introduced, replacing the Windows 2000 line of server products with a number of new features and a strong focus on security; this was followed in December 2005 by Windows Server 2003 R2. On January 30, 2007, Microsoft released Windows Vista. On October 22, 2009, Microsoft released Windows 7.
Invention and Development
Versions Available
| Windows Me | Windows 98 | Windows NT 4.0 | Windows 2000 | Windows Vista | Windows XP | Windows 7 |
Uses
Future
Windows 8, the successor to Windows 7, is currently in development. Microsoft posted a blog entry in Dutch on October 22, 2010 hinting that Windows 8 would be released in roughly 1 year. This Windows version will also be more suitable for tablets and netbooks, featuring a more touch-friendly interface. Several new features will also be introduced, such as support for USB 3.0 and the ability to run Windows from USB devices (like USB Hard Disks or USB Flash drives) with Windows To Go.
Why Use It?
According to Microsoft, Windows is the right choice because: Windows 7 gets you around your PC faster than ever, Type in the Start menu search box, and you'll see results instantly, grouped by category—documents, pictures, music, e‑mail, and programs. Sharing files and printers on your home network should be simple. Windows 7 has key performance improvements to take up less memory and run background services only when you need them. Connecting to wireless networks on your laptop—formerly a bit of a hassle—now takes just a couple of clicks. Use your fingers to browse the web, flip through photos, and open files and folders on a touchscreen PC—for the first time, Windows includes true multitouch technology. Device Stage, a new feature in Windows 7, works like a home page for things like portable music players, smartphones, and printers. Internet TV, part of Windows Media Center, gathers programming from sites all over the Internet—shows, sports highlights, video podcasts, and more. Windows 7 unleashes the full power of Internet Explorer 9, from its stunning hardware-accelerated graphics to the ability to launch favorite websites right from your taskbar. Action Center, new in Windows 7, puts you in control of maintenance and security messages. You can turn notifications on or off for things like Windows Defender or User Account Control.
Oracle
Linux: Oracle Linux, formerly known as Oracle Enterprise Linux, is a Linux distribution based on Red Hat Enterprise Linux, repackaged and sold by Oracle, available under the GNU General Public License (GPL) since late 2006.
Solaris: Solaris is a Unix operating system originally developed by Sun Microsystems. It superseded their earlier SunOS in 1993. Oracle Solaris, as it is now known, has been owned by Oracle Corporation since Oracle's acquisition of Sun in January 2010.
History
In 1987, AT&T and Sun announced that they were collaborating on a project to merge the most popular Unix variants on the market at that time: BSD, System V, and Xenix. This became Unix System V Release 4 (SVR4). On September 4, 1991, Sun announced that it would replace its existing BSD-derived Unix, SunOS 4, with one based on SVR4. The justification for this new "overbrand" was that it encompassed not only SunOS, but also the OpenWindows graphical user interface and Open Network Computing (ONC) functionality.
Invention and Development
Early releases of Solaris used OpenWindows as the standard desktop environment. Sun later dropped support for legacy SunView applications and NeWS with OpenWindows 3.3, which shipped with Solaris 2.3, and switched to X11R5 with Display Postscript support. Sun and other Unix vendors created an industry alliance to standardize Unix desktops. n 2001, Sun issued a preview release of the open-source desktop environment GNOME 1.4, based on the GTK+ toolkit, for Solaris 8. The underlying Solaris codebase has been under continuous development since work began in the late 1980s on what was eventually released as Solaris 2.0. The Solaris version under development by Sun since the release of Solaris 10 in 2005 is codenamed Nevada, and is derived from what is now the OpenSolaris codebase. In 2003, an addition to the Solaris development process was initiated. In 2007, Sun announced Project Indiana with several goals, including providing an open source binary distribution of the OpenSolaris project, replacing SXDE.The Solaris Express Community Edition (SXCE) was intended specifically for OpenSolaris developers. SXCE releases terminated with build 130 and OpenSolaris releases terminated with build 134 a few weeks later.
Versions Available
| 5.8 | 5.9 | 5.10 | 5.11 |
Uses
Solaris is known for its scalability, especially on SPARC systems, and for originating many innovative features such as DTrace, ZFS and Time Slider. Solaris supports SPARC-based and x86-based workstations and servers from Sun and other vendors, with efforts underway to port to additional platforms.
Future
Under Sun, the OpenSolaris open source effort can be used on standalone computers. It also represents the next generation of Solaris as a testbed for future technologies. Solaris primarily at the high end, it will go all the way down to the desktop for development. Solaris 11 is the future, and it will be the best release of Solaris ever.
Why Use It?
Oracle Solaris Zones is a virtualization mechanism that provides workloads with a private set of OS resources that are protected from each other. Sometimes referred to as "virtual servers," zones create the illusion that workloads are running virtually on their own machines, with a distinct set of OS resources that are visible to the applications. Solaris has long been optimized for use on large Symmetric Multiprocessing (SMP) systems, and Solaris 11 adds new refinements for increasing its performance on servers with very large numbers of cores. In Solaris 11, the mechanism for auditing system behavior has become much more efficient, and it is now turned on by default (in previous releases of Solaris, the auditing mechanism could slow performance, and it was therefore disabled by default). Solaris 11 introduces a new package management framework called Image Packaging System (IPS), which is designed to perform complete software life cycle management, ranging from installation to upgrades and removal of software packages.