1. The operating system (OS) can be considered as the most important program that runs on a computer. Every
general-purpose computer must have an operating system to provide a software platform on top of which other
programs (the application software) can run. It is also the main control program of a computer that schedules
tasks, manages storage, and handles communication with peripherals. The central module of an operating
system is the 'kernel'. It is the part of the operating system that loads first, and it remains in main memory.
Because it stays in memory, it is important for the kernel to be as small as possible while still providing all the
essential services required by other parts of the operating system and applications. Typically, the kernel is
responsible for memory management, process and task management, and disk management.
In general an application software must be written to run on top of a particular operating system. Your choice of
operating system, therefore, determines to a great extent the applications you can run. For PCs, the most
popular operating systems are Windows 95/98, MS-DOS (Microsoft-Disk Operating System), OS/2, but others
are available, such as Linux, BeOS…
For large systems, the operating system has even greater responsibilities and powers. It is like a traffic cop: it
makes sure that different programs and users running at the same time do not interfere with each other. The
operating system is also responsible for security, ensuring that unauthorized users do not access the system.
From this point of view, 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: Real time operating system (RTOS) responds to input instantly. General-purpose operating
systems, such as DOS and UNIX, are not real-time.
An OS is a 16-bit operating system if it processes 16 bits of data at once, e.g.: DOS. On the other hand,
Windows 98 and OS/2 Warp are 32-bit operating systems because they can process 32 bits of data at once.
A network operating system (NOS) is an operating system which makes it possible for computers to be on a
network, and manages the different aspects of the network. Some examples are Windows for Workgroups,
Windows NT, AppleTalk, DECnet, and LANtastic…
2. The two reason why we used six server computer in regional bank instead one super computer?
- We used six server computer it because six server is more memory than to super computer and six server computer is fastiest than to super computer.
- It because the six server computer is new model than to super computer.