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Types of Operating System
The important types of operating systems which are most commonly used.
Batch operating system
The users of a batch operating system do not interact with the computer directly. Each user
prepares his job on an off-line device like punch cards and submits it to the computer operator.
To speed up processing, jobs with similar needs are batched together and run as a group. The
programmers leave their programs with the operator and the operator then sorts the programs
with similar requirements into batches.
The problems with Batch Systems are as follows −
• Lack of interaction between the user and the job.
• CPU is often idle, because the speed of the mechanical I/O devices is slower than the CPU.
• Difficult to provide the desired priority.
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Time-sharing operating systems
Time-sharing is a technique which enables many people, located at various terminals, to use a
particular computer system at the same time. Time-sharing or multitasking is a logical extension
of multiprogramming. Processor's time which is shared among multiple users simultaneously is
termed as time-sharing.
The main difference between Multiprogrammed Batch Systems and Time-Sharing Systems is
that in case of Multiprogrammed batch systems, the objective is to maximize processor use,
whereas in Time-Sharing Systems, the objective is to minimize response time.
Multiple jobs are executed by the CPU by switching between them, but the switches occur so
frequently. Thus, the user can receive an immediate response. For example, in a transaction
processing, the processor executes each user program in a short burst or quantum of
computation. That is, if n users are present, then each user can get a time quantum. When the
user submits the command, the response time is in few seconds at most.
The operating system uses CPU scheduling and multiprogramming to provide each user with a
small portion of a time. Computer systems that were designed primarily as batch systems have
been modified to time-sharing systems.
Advantages of Timesharing operating systems are as follows −
• Provides the advantage of quick response.
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