Types Of operating system

Types of Operating Systems: Some of the widely used operating systems are as follows-
1. Batch Operating System –
This type of operating system do not interact with the
computer directly. There is an operator which takes
similar jobs having same requirement and group
them into batches. It is the responsibility of operator
to sort the jobs with similar needs.
Advantages of Batch Operating System:
It is very difficult to guess or know the time
required by any job to complete. Processors of the
batch systems knows how long the job would be
when it is in queue
Multiple users can share the batch systems
The idle time batch system is very less
It is easy to manage large work repeatedly in
batch systems
Disadvantages of Batch Operating System:
The computer operators should be well known with
batch systems
Batch systems are hard to debug
It is sometime costly
The other jobs will have to wait for an unknown
time if any job fails
Examples of Batch based Operating System:
Payroll System, Bank Statements etc.
2. Time-Sharing Operating Systems –
Each task has given some time to execute, so that all
the tasks work smoothly. Each user gets time of CPU
as they use single system. These systems are also
known as Multitasking Systems. The task can be from
single user or from different users also. 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
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
Data communication problem
Examples of Time-Sharing OSs are: Multics, Unix
etc.
3. Distributed Operating System –
These types of operating system is a recent
advancement in the world of computer technology
and are being widely accepted all-over the world
and, that too, with a great pace. Various autonomous
interconnected computers communicate each other
using a shared communication network. Independent
systems possess their own memory unit and CPU.
These are referred as
loosely coupled systems or
distributed systems. These systems processors differ
in sizes and functions. The major benefit of working
with these types of operating system is that it is
always possible that one user can access the files or
software which are not actually present on his
system but on some other system connected within
this network i.e., remote access is enabled within the
devices connected in that network.
Advantages of Distributed Operating System:
Failure of one will not affect the other network
communication, as all systems are independent
from each other
Electronic mail increases the data exchange speed
Since resources are being shared, computation is
highly fast and durable
Load on host computer reduces
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. Not only that the
underlying software is highly complex and not
understood well yet
Examples of Distributed Operating System are-
LOCUS etc.
4. Network Operating System –
These systems runs on a server and provides the
capability to manage data, users, groups, security,
applications, and other networking functions. These
type of operating systems allows shared access of
files, printers, security, applications, and other
networking functions over a small private network.
One more important aspect of Network Operating
Systems is that all the users are well aware of the
underlying configuration, of all other users within the
network, their individual connections etc. and that’s
why these computers are popularly known as
tightly
coupled systems.
Advantages of Network Operating System:
Highly stable centralized servers
Security concerns are handled through servers
New technologies and hardware up-gradation are
easily integrated to the system
Server access are possible remotely from different
locations and types of systems
Disadvantages of Network Operating System:
Servers are costly
User has to depend on central location for most
operations
Maintenance and updates are required regularly
Examples of Network Operating System are:
Microsoft Windows Server 2003, Microsoft Windows
Server 2008, UNIX, Linux, Mac OS X, Novell NetWare,
and BSD etc.
5. Real-Time Operating System –
These types of OSs serves the real-time systems. The
time interval required to process and respond to
inputs is very small. This time interval is called
response time.
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. These
systems are built for saving life like automatic
parachutes or air bags which are required to be
readily available in case of any accident. 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 Consumption: Maximum utilization of
devices and system,thus more output from all the
resources
Task Shifting: Time assigned for shifting tasks in
these systems are very less. For example in older
systems it takes about 10 micro seconds in shifting
one task to another and in latest systems it takes 3
micro seconds.
Focus on Application: Focus on running applications
and less importance to applications which are in
queue.
Real time operating system in embedded
system:
Since size of programs are small, RTOS
can also be used in embedded systems like in
transport and others.
Error Free: These types of systems are error free.
Memory Allocation: Memory allocation is best
managed in these type of systems.
Disadvantages of RTOS:
Limited Tasks: Very few task run at the same
time and their concentration is very less on few
applications to avoid errors.
Use heavy system resources: Sometimes the
system resources are not so good and they are
expensive as well.
Complex Algorithms: The algorithms are very
complex and difficult for the designer to write on.
Device driver and interrupt signals: It needs
specific device drivers and interrupt signals to
response earliest to interrupts.
Thread Priority: It is not good to set thread priority
as these systems are very less pron to switching
tasks.

SOURCE