Types of operating system with advantages and disadvantages:-

* Some of the widely used operating systems are as follows:-
   1. Batch operating system.
   2. Time-Sharing oprtaing system.
  3. Distributed operating system.
  4. Network operating system.
  5. Real-Time operating system.

1> Batch Operating System:- 
             This type of operating system does not directly interact with computer system. Each user prepares job on an offline device such as punch card and submmits to the computer operator.  There is an operator which takes similar jobs having same requirement and group them into batches.

* Advantages of Batch Operating System:-

•   Repeated jobs are done fast in batch systems without user interaction.
•   You don’t need special hardware and system support to input data in batch systems.
•   Best for large organizations but small organizations can also benefit from it.
•   Batch systems can work offline so it makes less stress on processor.
•   The idle time batch system is very less.
•  Multiple users can share the batch systems.
•   The batch systems can manage large repeated work easily.

•   You can assign specific time for the batch jobs so when the computer is idle it starts processing the   batch jobs i.e. at night or any free time.

•   It is very difficult to guess or know the time required by any job to complete , but processors of the batch systems know how long the job would be when it is in queue.

* Disadvantages of Batch Operating System:-

• The computer operators should be well trained with batch systems.
• Batch systems are hard to debug.
• Batch systems are sometime costly.
• The other jobs will have to wait for an unknown time if any other job fails.
• Lack of interaction between the user and the job.
• Difficult to provide desired priority.

* Examples of Batch based Operating System:- Payroll System, Bank Statements etc.

2 >Time-Sharing oprtaing system:-

               Time sharing operating system uses a technique  which enables many users located at   various terminals to use a particular computer system at the same time. The processor's time which   is shared among multiple users simultaneously is termed as time sharing. time sharing is also known   as multitasking. Each task is given some time to execute, so that all the tasks work smoothly. Each   user gets time of CPU as they use single system. The time that each task gets to execute is called   quantum. After this time interval is over OS switches over to next task.

* Advantages of Time-Sharing OS:-

• Each task gets an equal opportunity.
• Less chances of duplication of software.
• Advantages of quick responce.
• CPU idle time can be reduced.

* Disadvantages of Time-Sharing OS:-

• Reliability problem.
• One must have to take care of security and integrity of user programs and data.
• problem of data communication.
• Switching between tasks becomes sometimes sophisticated as there are lot of users and applications running which may hang up the system. 
• Time sharing systems should have high specifications of hardware.

* Examples of Time-Sharing OSs are:- Multics, Unix etc.

3> Distributed operating system:-

              Distributed Operating System is a model where distributed applications are running on multiple computers linked by communications. This type of OS use multiple central processors to serve multiple real time applications. Data processing jobs are distributed among the processors. Processors communicates with one another through various communication channels. Distributed systems may be different in size and functions.  It is always possible that one user can access the files which are not actually present on his system but on some other system connected within this network.

* Advantages of Distributed Operating System:-

• If one site fails the remaining sites can continue the operation , as all systems are independent from each other.
• Electronic mail increases the data exchange speed in this system.
• Since resources are being shared, computation is highly fast and durable.
• One site may be able to use the resources available at other site.
•  Reduces load on host computer.
• These systems are easily scalable as many systems can be easily added to the network
• Delay in data processing reduces.

* Disadvantages of Distributed Operating System:-

• Failure of the main network will stop the entire communication.
• To establish distributed systems the language which are used are not well defined yet.
• These types of systems are not readily available as they are very expensive. 

* Examples of Distributed Operating System are:- LOCUS etc.

4> Network operating system:- 

                   Network operating system run on a server and provide the capability to manage data, users, groups, security, applications, and other networking functions. All the users of this OS are well aware of the underlying configuration of all other users within the network and their individual connections. These computers are popularly known as tightly coupled systems.

* Advantages of Network Operating System:-

• Highly stable servers due to centralization.
• Security is handled through servers.
• New technologies and hardware up-gradation can be easily integrated into the system.
• Remote accessing of servers are also possible.

* Disadvantages of Network Operating System:-

• Servers are costly.
• User has to depend on central location for most operation.
• Regular maintainance and updates are required.

* Examples of Network Operating System are:- MsWindows Server 2003, MsWindows Server 2008, UNIX, Linux, Mac OS X, Novell NetWare, and BSD etc.

 5> Real-Time operating system:-

           Real-time systems are used when there are time requirements are very strict like missile systems, air traffic control systems, robots etc.

Two types of Real-Time Operating System which are as follows:-

Hard Real-Time Systems:- These OSs are meant for the applications where time constraints are very strict and even the shortest possible delay is not acceptable.  Virtual memory is almost never found in these systems.

Soft Real-Time Systems:-These OSs are for applications where for time-constraint is less strict.

      
* Advantages of RTOS:-

• Maximum utilization of devices and system,thus more output from all the resources.
• Time assigned for shifting tasks in these systems are very less.
• Focus on running applications and less importance to applications which are in queue.
• RTOS can also be used in embedded systems like in transport and others.
• These types of systems are error free.
• Memory allocation is best managed in these type of systems.

* Disadvantages of RTOS:-

• Very few tasks run at the same time and their concentration is very less on few applications to avoid errors.
• Sometimes the system resources are not so good and they are expensive as well.
• The algorithms are very complex and difficult for the designer to write on.
•  It needs specific device drivers and interrupt signals to response earliest to interrupts.

* Examples of Real-Time Operating Systems are:- Scientific experiments, industrial control systems, weapon systems, robots, air traffic control systems, etc.