1.What is an Operating system?
An operating system is a program that manages the computer hardware. It also provides a basis for application programs and act as an intermediary between a user of a computer and the computer hardware. It controls and coordinates the use of the hardware among the various application programs for the various users.
2.Why is the Operating System viewed as a resource allocator & control program?
A computer system has many resources - hardware & software that may be required to solve a problem, like CPU time, memory space, file-storage space, I/O devices & so on. The OS acts as a manager for these resources so it is viewed as a resource allocator.The OS is viewed as a control program because it manages the execution of user programs to prevent errors & improper use of the computer.
3. What is the Kernel?
A more common definition is that the OS is the one program running at all times on the computer, usually called the kernel, with all else being application programs.
4. What are Batch systems?
Batch systems are quite appropriate for executing large jobs that need little interaction. The user can submit jobs and return later for the results. It is not necessary to wait while the job is processed. Operators batched together jobs with similar needs and ran them through the computer as a group.
5. What is the advantage of Multiprogramming?
Multiprogramming increases CPU utilization by organizing jobs so that the CPU always has one to execute. Several jobs are placed in the main memory and the processor is switched from job to job as needed to keep several jobs advancing while keeping the peripheral devices in use. Multiprogramming is the first instance where the Operating system must make decisions for the users.Therefore they are fairly sophisticated.
