OPERASI DASAR KOMPUTER

RAHAYU DEWI NINGRUM

Dalam Ilmu komputer, Sistem operasi atau dalam bahasa Inggris: operating system atau OS adalah perangkat lunak sistem yang bertugas untuk melakukan kontrol dan manajemen perangkat keras serta operasi-operasi dasar sistem, termasuk menjalankan software aplikasi seperti program-program pengolah kata dan browser web.

Secara umum, Sistem Operasi adalah software pada lapisan pertama yang ditaruh pada memori komputer pada saat komputer dinyalakan. Sedangkan software-software lainnya dijalankan setelah Sistem Operasi berjalan, dan Sistem Operasi akan melakukan layanan inti umum untuk software-software itu. Layanan inti umum tersebut seperti akses ke disk, manajemen memori, skeduling task, dan antar-muka user. Sehingga masing-masing software tidak perlu lagi melakukan tugas-tugas inti umum tersebut, karena dapat dilayani dan dilakukan oleh Sistem Operasi. Bagian kode yang melakukan tugas-tugas inti dan umum tersebut dinamakan dengan "kernel" suatu Sistem Operasi.


Sistem operasi-sistem operasi utama yang digunakan komputer sistem umum (termasuk PC, komputer personal) terbagi menjadi 3 kelompok besar:

1. Keluarga Microsoft Windows - yang antara lain terdiri dari Windows Desktop Environment (versi 1.x hingga versi 3.x), Windows 9x (Windows 95, 98, dan Windows ME), dan Windows NT (Windows NT 3.x, Windows NT 4.0, Windows 2000, Windows XP, Windows Server 2003, Windows Vista, Windows 7 (Seven) yang akan dirilis pada tahun 2009, dan Windows Orient yang akan dirilis pada tahun 2014)).
2. Keluarga Unix yang menggunakan antarmuka sistem operasi POSIX, seperti SCO UNIX, keluarga BSD (Berkeley Software Distribution), GNU/Linux, MacOS/X (berbasis kernel BSD yang dimodifikasi, dan dikenal dengan nama Darwin) dan GNU/Hurd.
3. Mac OS, adalah sistem operasi untuk komputer keluaran Apple yang biasa disebut Mac atau Macintosh. Sistem operasi yang terbaru adalah Mac OS X versi 10.4 (Tiger). Awal tahun 2007 direncanakan peluncuran versi 10.5 (Leopard).

Sedangkan komputer Mainframe, dan Super komputer menggunakan banyak sekali sistem operasi yang berbeda-beda, umumnya merupakan turunan dari sistem operasi UNIX yang dikembangkan oleh vendor seperti IBM AIX, HP/UX, dll.



ENGLISH :

An operating system (commonly abbreviated to either OS or O/S) is an interface between hardware and user; an OS is responsible for the management and coordination of activities and the sharing of the resources of the computer. The operating system acts as a host for computing applications that are 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. 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.[1] Some of the oldest models may however use an embedded operating system, that may be contained on a compact disk or other data storage device.

Operating systems offer a number of services to application programs and users. Applications access these services through application programming interfaces (APIs) or system calls. By invoking these interfaces, the application can request a service from the operating system, pass parameters, and receive the results of the operation. Users may also interact with the operating system with some kind of software user interface (UI) like typing commands by using command line interface (CLI) or using a graphical user interface (GUI, commonly pronounced “gooey”). For hand-held and desktop computers, the user interface is generally considered part of the operating system. On large multi-user systems like Unix and Unix-like systems, the user interface is generally implemented as an application program that runs outside the operating system. (Whether the user interface should be included as part of the operating system is a point of contention.)

Common contemporary operating system families include BSD, Darwin (Mac OS X), GNU/Linux, SunOS (Solaris/OpenSolaris), and Windows NT (XP/Vista/7). While servers generally run Unix or some Unix-like operating system, embedded system markets are split amongst several operating systems

Microsoft Windows
Windows Vista is the latest stable Windows operating system.

Microsoft Windows is a family of proprietary operating systems that originated as an add-on to the older MS-DOS operating system for the IBM PC. Modern versions are based on the newer Windows NT kernel that was originally intended for OS/2. Windows runs on x86, x86-64 and Itanium processors. Earlier versions also ran on the DEC Alpha, MIPS, Fairchild (later Intergraph) Clipper and PowerPC architectures (some work was done to port it to the SPARC architecture).

As of June 2008, Microsoft Windows holds a large amount of the worldwide desktop market share. Windows is also used on servers, supporting applications such as web servers and database servers. In recent years, Microsoft has spent significant marketing and research & development money to demonstrate that Windows is capable of running any enterprise application, which has resulted in consistent price/performance records (see the TPC) and significant acceptance in the enterprise market.

The most widely used version of the Microsoft Windows family is Windows XP, released on October 25, 2001.

In November 2006, after more than five years of development work, Microsoft released Windows Vista, a major new operating system version of Microsoft Windows family which contains a large number of new features and architectural changes. Chief amongst these are a new user interface and visual style called Windows Aero, a number of new security features such as User Account Control, and a few new multimedia applications such as Windows DVD Maker. A server variant based on the same kernel, Windows Server 2008, was released in early 2008.

Windows 7 is currently under development; Microsoft has stated that it intends to scope its development to a three-year timeline; it is to be released on October 22, 2009.

[edit] Unix and Unix-like operating systems
Debian is a (linux-based) unix-like system

Ken Thompson wrote B, mainly based on BCPL, which he used to write Unix, based on his experience in the MULTICS project. B was replaced by C, and Unix developed into a large, complex family of inter-related operating systems which have been influential in every modern operating system (see History). The Unix-like family is a diverse group of operating systems, with several major sub-categories including System V, BSD, and Linux. The name "UNIX" is a trademark of The Open Group which licenses it for use with any operating system that has been shown to conform to their definitions. "Unix-like" is commonly used to refer to the large set of operating systems which resemble the original Unix.

Unix-like systems run on a wide variety of machine architectures. They are used heavily for servers in business, as well as workstations in academic and engineering environments. Free Unix variants, such as GNU, Linux and BSD, are popular in these areas.

Some Unix variants like HP's HP-UX and IBM's AIX are designed to run only on that vendor's hardware. Others, such as Solaris, can run on multiple types of hardware, including x86 servers and PCs. Apple's Mac OS X, a hybrid kernel-based BSD variant derived from NeXTSTEP, Mach, and FreeBSD, has replaced Apple's earlier (non-Unix) Mac OS.

Unix interoperability was sought by establishing the POSIX standard. The POSIX standard can be applied to any operating system, although it was originally created for various Unix variants.

[edit] Mac OS X
Mac OS X "Leopard"

Mac OS X is a line of proprietary, graphical operating systems developed, marketed, and sold by Apple Inc., the latest of which is pre-loaded on all currently shipping Macintosh computers. Mac OS X is the successor to the original Mac OS, which had been Apple's primary operating system since 1984. Unlike its predecessor, Mac OS X is a UNIX operating system built on technology that had been developed at NeXT through the second half of the 1980s and up until Apple purchased the company in early 1997.

The operating system was first released in 1999 as Mac OS X Server 1.0, with a desktop-oriented version (Mac OS X v10.0) following in March 2001. Since then, five more distinct "end-user" and "server" editions of Mac OS X have been released, the most recent being Mac OS X v10.5, which was first made available in October 2007. Releases of Mac OS X are named after big cats; Mac OS X v10.5 is also called "Leopard". The next version of OS X, named "Snow Leopard" will be released in September 2009.

The server edition, Mac OS X Server, is architecturally identical to its desktop counterpart but usually runs on Apple's line of Macintosh server hardware. Mac OS X Server includes work group management and administration software tools that provide simplified access to key network services, including a mail transfer agent, a Samba server, an LDAP server, a domain name server, and others.

[edit] Plan 9

Ken Thompson, Dennis Ritchie and Douglas McIlroy at Bell Labs designed and developed the C programming language to build the operating system Unix. Programmers at Bell Labs went on to develop Plan 9 and Inferno, which were engineered for modern distributed environments. Plan 9 was designed from the start to be a networked operating system, and had graphics built-in, unlike Unix, which added these features to the design later. Plan 9 has yet to become as popular as Unix derivatives, but it has an expanding community of developers. It is currently released under the Lucent Public License. Inferno was sold to Vita Nuova Holdings and has been released under a GPL/MIT license.

[edit] Real-time operating systems
Main article: real-time operating system

A real-time operating system (RTOS1) is a multitasking operating system intended for applications with fixed deadlines (real-time computing). Such applications include some small embedded systems, automobile engine controllers, industrial robots, spacecraft, industrial control, and some large-scale computing systems.

An early example of a large-scale real-time operating system was Transaction Processing Facility developed by American Airlines and IBM for the Sabre Airline Reservations System.

[edit] Embedded systems
Main article: list of operating systems#Microcontroller, Real-time

Embedded systems use a variety of dedicated operating systems. In some cases, the "operating system" software is directly linked to the application to produce a monolithic special-purpose program. In the simplest embedded systems, there is no distinction between the OS and the application.

Embedded systems that have fixed deadlines use a real-time operating system such as VxWorks, eCos, QNX, MontaVista Linux and RTLinux.

Some embedded systems use operating systems such as Symbian OS, Palm OS, Windows CE, BSD, and Linux, although such operating systems do not support real-time computing.

Windows CE shares similar APIs to desktop Windows but shares none of desktop Windows' codebase[citation needed].

[edit] Hobby development

Operating system development, or OSDev for short, as a hobby has a large cult-like following. As such, operating systems, such as Linux, have derived from hobby operating system projects. The design and implementation of an operating system requires skill and determination, and the term can cover anything from a basic "Hello World" boot loader to a fully featured kernel. One classical example of this is the Minix Operating System—an OS that was designed by A.S. Tanenbaum as a teaching tool but was heavily used by hobbyists before Linux eclipsed it in popularity.

[edit] Other

Older operating systems which are still used in niche markets include OS/2 from IBM and Microsoft; Mac OS, the non-Unix precursor to Apple's Mac OS X; BeOS; XTS-300. Some, most notably AmigaOS 4 and RISC OS, continue to be developed as minority platforms for enthusiast communities and specialist applications. OpenVMS formerly from DEC, is still under active development by Hewlett-Packard. There were a number of operating systems for 8 bit computers - Apple's DOS (Disk Operating System) 3.2 & 3.3 for Apple II, ProDOS, UCSD, CP/M - available for various 8 and 16 bit environments.

Research and development of new operating systems continues. GNU Hurd is designed to be backwards compatible with Unix, but with enhanced functionality and a microkernel architecture. Singularity is a project at Microsoft Research to develop an operating system with better memory protection based on the .Net managed code model. Systems development follows the same model used by other Software development, which involves maintainers, version control "trees",[8] forks, "patches", and specifications. From the AT&T-Berkeley lawsuit the new unencumbered systems were based on 4.4BSD which forked as FreeBSD and NetBSD efforts to replace missing code after the Unix wars. Recent forks include DragonFly BSD and Darwin from BSD Unix.[9]