An Operating system is a group of programs that enables a user to interact with the computer hardware’s like CPU(central processing unit), Keyboard, Mouse, printers, modem, external drive, etc.
Without any OS(operating system) no one can use the computer or mobile device. Every computer or mobile system should have at least one operating system installed to run other programs like internet browsing, document editing, watching or listening to any media, doing calculations, Playing games.
Types Of Operating Systems:
There are mainly two types of OS available in the market one for Computer systems and one for mobile devices. Although the basic functionality is the same some features are different between the two.
There are many types of operating systems and can be divided into different categories, but mainly are two types…
- Single User OS: Only one person can use the computer at one time.
- Multiple user OS: Multiple users can work with one or more people at a time. Multiple user OS is used where people have to work in conjunction.
But in terms of features, usability, and execution OS can be defined into these seven categories………
- Batch Operating System
- Time-Sharing OS
- Multiprocessing OS
- Distributed OS
- Real-time OS
- Network OS
- Mobile OS
The batch operating system was used in the era of the 1970s. This type of operating system does not interact with the computer directly. Each user prepares his job on an offline device like punch cards and submits it to the computer operator.
To speed up processing jobs, similar needs are batched together and run as a group. It is the responsibility of the computer operator to sort, run and execute jobs accordingly.
The system puts all the jobs in a queue based on first come first serve and then executes the jobs one by one. The user collects their respective output when all the jobs get executed.
Advantages of Batch Operating System:
- The overall time taken by the system to execute all the programs will be reduced.
- It is very difficult to guess or know the time required for any job to complete. Processors of the batch systems know how long the job would be when it is in the queue.
- The batch operating system can be shared between multiple users.
- The ideal time for the batch system is very less.
- It is easy to manage large work repeatedly in batch systems.
Disadvantages of batch OS:
- If there are five jobs Job1 Job2,3,4 and 5 present in the batch. If the execution time of Job1 is very high then the other four jobs will never be going to get executed hence the other processes get delayed.
- Batch processing is not suitable for jobs that are dependent on the user’s input. If a job requires the input of two numbers from the console then it will never be going to execute because at the time of execution the user is absent.
- The computer operators should be debugged with batch systems. Batch systems are hard to debug.
Time-sharing is a technique that enables multiple people, located at different terminals, and using one computer system simultaneously. Each task is given some time to execute so that all the tasks work smoothly.
These systems are also known as Multitasking Systems. The tasks are given to a single user or different users. The time that each task gets to execute is called quantum. After, this time interval is over OS switches over to the next task.
Advantages Of Time Sharing OS:
- Equal time quantum gave to each process so every process gets equal opportunity to execute.
- Reduce the chance of duplication of software.
- The CPU utilization is very high so reduce the idle time of the CPU.
Disadvantages of Time-sharing OS:
- The Higher priority tasks are never going to execute first because the equal opportunity is given to each process.
- The security and integrity of user programs and data are very low.
- The problem in data communication.
- Reliability issue.
In Multiprocessing, Parallel computing is achieved. There is more than one processor present in the system that can execute more than one process simultaneously.
Advantages Of Multiprocessing OS:
- CPU executes multiple processes at a time which increases the throughput of the system.
Disadvantages of Multiprocessing OS:
- Still, the priority execution is not achieved.
In a Distributed Operating System, we have various systems and all these systems have their CPU, main memory, secondary memory, and resources. These systems are connected using a shared communication network.
Distributed systems use multiple central processors to serve multiple real-time applications and multiple users. Here, each system can perform its task individually.
Independent systems possess their memory unit and CPU. These are referred to as loosely coupled systems or distributed systems. Network file sharing is very much possible in distributed OS. Suppose a user is unable to find a file in his system but if that file is available in another system within the network user was able to access the file instantly.
Advantages of Distributed OS:
- Since the systems are connected so, the failure of one system can’t stop the execution of processes because other systems can do the execution.
- With a resource-sharing facility, a user at one site may be able to use the resources available at another.
- Electronic mail helps to speed up data delivery.
- The host computer is having less load to handle so better response time.
- Data processing is much faster.
- Customers are getting better service altogether.
Disadvantages of Distributed OS:
- Since the data is shared among all the computers, so the security of data is a big concern.
- If there is a problem in the communication network then the whole communication will be broken.
- To establish the distributed system all the systems must understand the communication language otherwise they are unable to connect.
An Embedded Operating System is designed to perform a specific task for a particular device that is not a computer. For example, the software used in elevators is dedicated to the working of elevators only and nothing else. The Embedded Operating System allows the access of device hardware to the software that is running on the top of the Operating System.
Advantages Of Embedded OS:
- The execution speed is very high because it acts on a particular job at a time.
- The cost is low compared to others.
- These systems consume low memory and all computing resources.
Disadvantages of Embedded OS:
- Only one job is performed at a time.
- It’s very difficult to upgrade the system also not scalable.
Real-time Operating Systems are used in the situation where we are dealing with some real-time data. So, whenever the data comes for execution it processes immediately.
There is no buffering so execution happens with almost zero delays. Real-time OS is a time-sharing system that is based on the concept of clock interrupt.
So, whenever you want to process any requests in a very short period, then you should use Real-time Operating System.
Real-time systems are used when there are time requirements that are very strict like missile systems, air traffic control systems, robots, etc.
There are two types of real-time operating systems.
Hard Real-time Systems:
Whenever we want to perform a critical task with almost zero delays in response we use this type of OS. Like immediately opening a parachute or airbags in case of an accident.
Hard real-time systems guarantee that critical tasks are completed on time. In hard real-time systems, secondary storage is limited or missing and the data is stored in ROM(Read Only Memory). In these systems, virtual memory is rarely found.
Soft Real-time Systems:
When we need real-time access to data but response time is not extremely important we use soft real-time OS.
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 OS:
- In real-time OS maximum utilization of all resources in a system happened.
- The time assigned for any shifting task is very less compared to old systems. In the old day’s system needs 10 microseconds to execute but in the real-time OS, it comes down to 3 microseconds.
- There is more focus on the running application which is more important and all the less important applications are in queue mode by default.
- A real-time operating system in the embedded system: Since the size of programs is small, It can also be used in embedded systems like in transport and others.
- These types of systems are almost error-free.
- Memory allocation is managed wonderfully in these systems.
Disadvantages of Real-Time OS:
- A small number of tasks are executed at a time to make the system error-free. So the concentration of tasks is very low compared to other systems.
- The algorithms are very complex and difficult for the designer to work with it.
- Sometimes these systems need specific drivers and interrupt signals to respond quickly so the dependency is there.
- The system resources are not so good and they are expensive as well.
- These systems are very less prone to switching tasks.
This type of operating system runs on servers and is built for serving a specific job role or group of jobs at a time. Network OS gives 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.
All the users are well aware of the underlying configuration, of all other users within the network, their connections, that’s why these systems are known as tightly coupled systems.
Types of network operating systems:
- Peer-to-peer network operating system: The type of network operating system that allows users to share files, resources between two or more computer machines using a LAN.
- Client-Server network operating system: It is the type of network operating system that allows the users to access resources, functions, and applications through a common server or center hub of the resources. The client workstation can access all resources that exist in the central hub of the network. Multiple clients can access and share different types of resources over the network from different locations.
Advantages of Network OS:
- High stability because of centralized servers.
- Security concerns are taken care of by servers more efficiently.
- New technologies and hardware up-gradation are easily possible in these integrated systems.
- Remote server access is possible from different location makes the system more accessible and affordable.
Disadvantages Of Network OS:
- Users have to depend on a central location for most operations.
- Servers are very costly to integrate.
- Maintenance and upgrades are required regularly for smooth operations.
A mobile operating system (mobile OS) is an OS built exclusively for a mobile device, such as a smartphone, personal digital assistant (PDA), tablet, or other embedded mobile OS.
Popular mobile operating systems are Android, Symbian, iOS, BlackBerry OS, and Windows Mobile.
A mobile OS is responsible for identifying and defining mobile device features and functions, including keypads, application synchronization, email, thumbwheel, and text messaging.
A mobile OS is similar to a standard OS (like Windows, Linux, and Mac) but is relatively simple and light and primarily manages the wireless variations of local and broadband connections, mobile multimedia, and various input methods.
Advantages of Mobile OS:
- It’s highly customizable, easy to use and multiple applications are available for the mobile OS which are ready-made.
- It is a low cost compared to computer OS and is best for normal use.
- Different manufacturers create different models so we have a huge range to choose from. High to low all types of products are available for all range of users.
- Some OS like Android is OPEN SOURCE and highly CUSTOMIZABLE.
- IOS from Apple are Known for their UI experience, Design, and Style, Build quality, Security, Application availability in their app store, Less vulnerable to viruses and malware, Frequent updates and software, and customer support.
Disadvantages Of Mobile OS:
- Some mobile OS is very costly like Blackberry OS, IOS.
- IOS like IOS Blackberry are fully dependent on their manufacturer so that creates a monopoly in the market.
- OS like Android is less secure made it more vulnerable to viruses and malware.
- Lots of fake apps are developed intentionally to cheat users which is a major concern in mobile OS.
- Upgrade and update are not frequent in some mobile OS, making them outdated and prone to security flaws.