WHAT Is an operating system? An operating system is a program designed to run other programs on a computer. A computer’s operating system is its most important program. It is considered the backbone of a computer, managing both software and hardware resources. Operating systems are responsible for everything from the control and allocation of memory to recognizing input from external devices and transmitting output to computer displays. They also manage files on computer hard drives and control peripherals, like printers and scanners.
Where might you find an operating system? You can find operating systems in a lot of todays gadgets such as mobile phones like Blackberry’s, IPhone's and the HTC android, and there are also different types of OS’s like the mac, windows xp, windows 98 and it goes on.. There even in our game consoles. All major computer platforms (hardware and software) require and sometimes include an operating system. Linux, Windows 2000, VMS, OS/400, AIX, and z/OS are all examples of operating systems.
What’s there main function? The basic unit of software that the operating system deals with in scheduling the work done by the processor is either a process or a thread, depending on the operating system. It's tempting to think of a process as an application, but that gives an incomplete picture of how processes relate to the operating system and hardware. The application you see (word processor or spreadsheet or game) is, indeed, a process, but that application may cause several other processes to begin, for tasks like communications with other devices or other computers. There are also numerous processes that run without giving you direct evidence that they ever exist. A process, then, is software that performs some action and can be controlled -- by a user, by other applications or by the operating system.
USER INTERFACE The junction between a user and a computer program. An interface is a set of commands or menus through which a user communicates with a program. A command-driven interface is one in which you enter commands. A menu-driven interface is one in which you select command choices from various menus displayed on the screen.
Memory MAnagement During the boot process, the operating system of our imaginary computer is designed to go to the top of available memory and then "back up" far enough to meet the needs of the operating system itself. Let's say that the operating system needs 300 kilobytes to run. Now, the operating system goes to the bottom of the pool of RAM and starts building up with the various driver software required to control the hardware subsystems of the computer. In our imaginary computer, the drivers take up 200 kilobytes. So after getting the operating system completely loaded, there are 500 kilobytes remaining for application processes.
Device management Most of the devices would normally be on or installed on the motherboard. The devices range from Processors, Memory, Input and output systems etc. Click on a link on the left frame for a closer look at each component listed.