Types of Operating Systems
Operating systems are there from the very first
computer generation and they keep evolving with time. In this chapter, we will
discuss some of the important types of operating systems which are most
commonly used. An Operating System performs
all the basic tasks like managing files, processes, and memory. Thus operating
system acts as the manager of all the resources, i.e. resource manager.
Thus, the operating system becomes an interface between user and machine. An
operating system is a well-organized collection of programs that manages the
computer hardware. It is a type of system software that is responsible for the
smooth functioning of the computer system. One of the important parts of this evolution
is the types of
operating system. There are some of
these different kinds of operating system as followings namely:
Operating Systems have been around now for over half a century. During this time, quite variety of them developed, not all of them widely known. In this tutorial we will briefly touch upon some kinds of these. An Operating System performs all the basic tasks like managing files, processes, and memory. Thus operating system acts as the manager of all the resources, i.e. resource manager.
{tocify} $title= {Table
of Contents}
Types of Operating
Systems: Some widely used operating systems are as follows-
1. Batch Operating System:-
 |
| Batch Operating Systems |
In
this type of operating system, users didn’t interact with the OS directly. Jobs were prepared on an offline device such as a punch card and were then. Submitted to the computer operator. To speed up processing, the users left their programs with the operator. This operator took the jobs with similar
requirements and grouped them into batches and then ran them as a group. The
users of a batch operating system do not interact with the computer directly.
This type of operating system does not interact with the computer directly.
There is an operator which takes similar jobs having the same requirement and
groups them into batches. It is the responsibility of the operator to sort jobs
with similar needs. In the 1970s,
Batch processing was very popular. In this technique, similar types of jobs
were batched together and executed in time. People
were used to having a single computer which was called a mainframe. In
Batch operating system, access is given to more than one person; they submit
their respective jobs to
the system for the execution.
The system put all of the jobs in a
queue on the basis of first come first serve and then executes the jobs one by one. The users collect their
respective output when all the jobs get executed. The
purpose of this operating system was mainly to transfer control from one job to
another as soon
as the job was completed. It contained a small set of programs called the
resident monitor that always
resided in one part of the main memory. The remaining part is used for
servicing jobs.
 |
Selection of the job for execution 2. Time-Sharing Operating Systems |
 |
| Time-sharing Operating Systems The main difference between Multiprogrammed Batch Systems and
Time-Sharing Systems is that A time-sharing operating system allows many users to be served
simultaneously, so sophisticated CPU scheduling schemes and Input/output
management are required. Time-sharing operating systems are very difficult and
expensive to build. Advantages
of Time-Sharing OS:
·
Each task gets an equal opportunity ·
Fewer chances of duplication of software ·
CPU idle time can be reduced ·
Provides the advantage of quick response. ·
Avoids duplication of software. ·
The time-sharing operating system provides
effective utilization and sharing of resources. Disadvantages of Time-Sharing OS:·
Reliability problem ·
One must have to take care of the security and integrity of user programs
and data ·
Data communication problem ·
Question of Security and Integrity of user’s programs and data. ·
Data transmission rates are very high in
comparison to other methods. ·
Security and integrity of user programs loaded
in memory and data need to be maintained as many users access the system at the
same time. Examples of Time-Sharing OSs are: Multics, UNIX, etc.
3. Distributed
Operating Systems:-
These types of the operating
system are 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 with each other using a
shared communication network. Independent systems possess their own memory unit
and CPU. These are referred to as loosely coupled systems or distributed
systems. These system’s processors differ in size and function. The major
benefit of working with these types of the 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 some other system connected within this
network i.e., remote access is enabled within the devices connected in that
network. The Distributed Operating system is not installed
on a single machine, it is divided into parts, and these parts are loaded on
different machines. A part of the distributed Operating system is installed on
each machine to make their communication possible. Distributed Operating
systems are much more complex, large, and sophisticated than Network operating
systems because they also have to take care of varying networking protocols.   |
Advantages of Distributed Operating System
- The
distributed operating system provides sharing of resources.
- This
type of system is fault-tolerant.
- 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
- Protocol overhead can dominate
computation cost.
- Failure of the main network will stop the entire communication
- To establish distributed systems the language which is 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 run on a server
and provide the capability to manage data, users, groups, security, applications,
and other networking functions. These types of operating systems allow 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.
An Operating system, which includes software and
associated protocols to communicate with other computers via a network
conveniently and cost-effectively, is called Network Operating System.
A
Network Operating System runs on a server and provides the server the
capability to manage data, users, groups, security, applications, and other
networking functions. The primary purpose of the network operating system is to
allow shared file and printer access among multiple computers in a network,
typically a local area network (LAN), a private network or to other networks.
Examples of network operating systems include
Microsoft Windows Server 2003, Microsoft Windows Server 2008, UNIX, Linux, Mac
OS X, Novell NetWare, and BSD.
Advantages of Network Operating System
- In
this type of operating system, network traffic reduces due to the division
between clients and the server.
- This
type of system is less expensive to set up and maintain.
- Centralized servers are highly
stable.
- Security is server managed.
- Upgrades to new technologies and hardware
can be easily integrated into the system.
- Remote access to servers is
possible from different locations and types of systems.
Disadvantages of Network Operating System
- In
this type of operating system, the failure of any node in a system affects
the whole system.
- Security
and performance are important issues. So trained network administrators
are required for network administration.
- High cost of buying and running a
server.
- Dependency on a central location
for most operations.
- Regular maintenance and updates
are required.
5. Multiprogramming Operating System-
Multiprogramming is an extension to batch processing where the CPU is always kept busy. Each process needs two types of system time: CPU time and IO time.
In a multiprogramming environment, when a process does its
I/O, The CPU can start the execution of other processes. Therefore,
multiprogramming improves the efficiency of the system.
Advantages of Multiprogramming OS
- Throughout
the system, it increased as the CPU always had one program to execute.
- Response
time can also be reduced.
Disadvantages of Multiprogramming OS
Multiprogramming systems provide an environment in which various systems resources are used efficiently, but they do not provide any user interaction with the computer system.
6. Multiprocessing Operating System:-
In Multiprocessing, Parallel computing is
achieved. There are more than one processors present in the system which can
execute more than one process at the same time. This will increase the
throughput of the system.
Advantages of
Multiprocessing operating system:
- Increased reliability: Due to the multiprocessing
system, processing tasks can be distributed among several processors. This
increases reliability as if one processor fails, the task can be given to
another processor for completion.
- Increased throughout: As several processors
increase, more work can be done in less.
Disadvantages of Multiprocessing operating System:
- Multiprocessing operating
system is more complex and sophisticated as it takes care of multiple CPUs
simultaneously.
7. Multitasking Operating Systems:-
 |
| Multitasking Operating System |
The
multitasking operating system is a logical extension of a multiprogramming
system that enables multiple programs
simultaneously. It allows a user to perform more than one computer task at the
same time.
Advantages of Multitasking operating system
- This operating system is more
suited to supporting multiple users simultaneously.
- The multitasking operating
systems have well-defined memory management.
Disadvantages of Multitasking operating system
- The multiple
processors are busier at the same time to complete any task in a
multitasking environment, so the CPU generates more heat.
8. Real Time Operating System:-
 |
| Real Time Operating Systems |
In Real-Time Systems, each job carries a certain
deadline within which the job is supposed to be completed, otherwise, the huge
loss will be there, or even if the result is produced, it will be completely
useless.
A real-time
system is defined as a data processing system in which the time interval
required to process and respond to inputs is so small that it controls the
environment. The time taken by the system to respond to an input and display of
required updated information is termed as the response time. So in
this method, the response time is very less as compared to online processing.
The Application of a Real-Time system exists in the case of military
applications, if you want to drop a missile, then the missile is supposed to be
dropped with a certain precision.
Real-time
systems are used when there are rigid time requirements on the operation of a
processor or the flow of data and real-time systems can be used as a control
device in a dedicated application. A real-time operating system must have
well-defined, fixed time constraints, otherwise the system will fail. For
example, scientific experiments, medical are imaging systems, industrial
control systems, weapon systems, robots, air traffic control systems, etc.
There are two
types of real-time operating systems.
Hard
real-time systems
Hard
real-time systems guarantee that critical tasks complete on time. In hard
real-time systems, secondary storage is limited or missing and the data is
stored in ROM. In these systems, virtual memory is almost never found.
Soft
real-time systems
Soft
real-time systems are less restrictive. A critical real-time task gets priority
over other tasks and retains the priority until it completes. Soft real-time
systems have limited utility than hard real-time systems. For example,
multimedia, virtual reality, Advanced Scientific Projects like undersea
exploration and planetary rovers, etc.
Advantages of Real-time operating system:-
- Easy to layout, develop and
execute real-time applications under the real-time operating system.
- In a Real-time operating
system, the maximum utilization of devices and systems.
- Maximum
Consumption: Maximum utilization of devices and system, thus
more output from all the resources.
- Task
Shifting: The time assigned for shifting tasks in these
systems are very less. For example, in older systems, it takes about 10
microseconds in shifting one task to another, and in the latest systems,
it takes 3 microseconds.
- Focus
on Application: Focus on running applications and less
importance to applications which are in the queue.
- Real-time operating
system in the embedded system: Since the 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
types of systems.
Disadvantages of Real-time operating system:-
- Real-time operating systems
are very costly to develop.
- Real-time operating systems
are very complex and can consume critical CPU cycles.
o
Limited Tasks: Very few tasks 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 interrupts signals to respond earliest
to interrupts.
- Thread Priority: It is not good to set thread priority as these
systems are very less prone to switching tasks.
Examples of Real-Time Operating
Systems are:
Scientific experiments, medical imaging systems, industrial control systems, weapon systems, robots, air traffic control systems, etc.
Examples
of Operating System
Following are some examples of
Operating Systems:
1.
Microsoft
Windows
it is a series of graphical operating systems developed, marketed, and sold by Microsoft. The first version of Windows was
released in 1985 as a GUI add-on to MS-DOS. The first version of Windows sold
as a standalone operating system was Windows 95.
2.
macOS
It is a series of graphical operating systems
developed by Apple Inc. It is the successor to Mac OS X, and it is the
operating system that powers Apple’s Mac family of computers.
3.
Linux
Linux is built around the Linux kernel and is
a free and open-source software operating system. It is one of the most popular
operating systems for servers and embedded devices. It is also used by millions
of desktop users around the world.
4.
Android
It is a mobile operating system developed by
Google. It is based on the Linux kernel and designed primarily for touch screen
mobile devices such as Smartphone and tablets.
5.
iOS
Another example of a mobile operating system
developed by Apple Inc. iOs is the successor to iPhone OS. It is an operating
system that powers the iPhone, iPad, and iPod Touch products.
Advantages of Operating System
There are several advantages of operating
systems. We have listed some of them below:
1.
Ensuring correct and
efficient use of the computer’s hardware.
2.
Allowing different
applications to run concurrently.
3.
Managing files and
folders.
4.
Providing a user
interface.
5.
Managing security.
6.
Managing resources.
7.
Managing printing.
8.
Providing a platform for
software development.
Disadvantages of Operating System
There are several disadvantages of operating
systems. We have listed some of them below:
·
They can be complex and
difficult to use.
·
They can be expensive to
purchase and maintain.
·
They can be vulnerable to
attack from malicious users.
Above were the major types of
Operating System. These are usually used in devices like desktops, PCs, etc…
Apart from these five, there are some other types of Operating System too that
are more familiar to people. These include:
1. Mobile Operating System
2. Embedded Operating System
3. Multiprogramming Operating System
4. Multiprocessor Operating System
5. Desktop Operating System
6. Clustered Operating System
7. Handheld Operating System
1. Mobile operating system
This OS is designed especially for
powering smartphones, tablets, and wearables devices. Some common OS are
Android, iOS, BlackBerry, Web, and watchOS. A
mobile OS is an operating system for smartphones, tablets, and PDA’s. It is a
platform on which other applications can run on mobile devices.
Some
most famous mobile operating systems are Android and iOS, but others include
BlackBerry, Web, and watchOS.
Advantages of Mobile OS
·
It provides
an ease to users.
Disadvantages of Mobile OS
·
Some of the
mobile operating systems give poor battery quality to users.
·
Some of the
mobile operating systems are not user-friendly.
Examples of
the Mobile OS: Android
OS, ios, Symbian OS, and Windows mobile OS.
2. Embedded Operating System
This OS performs a specific task
for a particular device but this device can be anything but not a computer.
Some common examples of this are elevators, GPS systems, fitness trackers, etc…
It allows the device hardware to access the software running on the OS. Though
only one task can be performed on this OS, it is fast, cheap and consumes less
memory and resources.
3. Multiprogramming Operating System
In this, the multiple tasks are
stored in the system memories that are acquired from the job pool and the OS
picks one task and starts executing it. Then, when the current job requires an
I/O, the OS fetches another job from the memory. In the case of multiple jobs
in ready state, which job to choose is decided through the process of CPU
Scheduling. It makes sure that the CPU is never left idle and focuses on
maximizing the CPU usage.
Time-Sharing OS is an extension to
the multiprogramming operating system. The only difference between these two is
that this OS focuses on increasing processor use whereas the other focuses on
decreasing the response time.
4. Multiprocessor Operating System
As the name suggests, this OS
consists of multiple processors that share a common physical memory and that
operate under a single OS. The system divides a task into subtasks which are
executed parallely in different processors. It provides high computing power
and increased system throughput and speed. Working of these processors is
transparent to the users.
5. Desktop Operating System
This OS focuses on increasing user
convenience and system responsiveness. Microsoft Windows and the Apple
Macintosh are two examples of this OS. This helped the microcomputers adapt
some of the technologies developed for larger operating systems and also
reduced the hardware costs.
6. Clustered Operating System
In this OS, a cluster of CPUs is
formed to accomplish computational work. The systems share storage and are
closely linked through a LAN network. A cluster software runs on nodes where
each node monitors one or more other nodes. If any failure occurs in the
monitored machine, the monitoring machine takes ownership of its storage, and
restarts the application(s) running on that node.
There are three types of
clustering. Asymmetric clustering where one machine (host) monitors the active
server while the other is running the applications. If the running machine
fails, the host machine takes over the active server. Symmetric clustering
where two or more hosts run applications while monitoring each other. It uses
all the available hardware. Parallel clustering where multiple hosts access the
same data on the shared storage.
7. Handheld Operating System
Handheld systems are usually
cellular phones with connection to a network like the Internet, Bluetooth with
limited size, small physical memory, slow processors, and small display
screens. The memory size usually being between 512 KB and 8 MB, the OS needs to
manage the memory efficiently and return the allocated memory back to the
memory manager when not in use. These are usually used for sending emails and
web browsing.
Summary:-
An OS is an interface that helps the user communicates with a
system. We have seen various types of Operating systems and their features. As the need for technology grows day by day in the
coming days and as younger generations like Gen Alpha grow up & join the
workforce good & efficient operating system will be the topmost priority of
every business setting. If you are planning to get a degree in IT, now is the best time to start.