Code360 powered by Coding Ninjas X Code360 powered by Coding Ninjas X
Table of contents
Operating System Generations
First Generation ( 1945 - 1955 ): Vacuum Tubes and Plugboards
Second Generation ( 1955 - 1965 ): Transistors and Batch Systems
Third Generation ( 1965 - 1980 ): Integrated Circuits and Multiprogramming
Fourth Generation ( 1980 - Present ): Personal Computers
What is the Generation of Operating Systems?
Types of Operating System
Frequently Asked Questions
Which OS is used in 4th generation?
How does the OS generation evolve?
What is the generation of operating system?
What is the 5th generation operating system?
What are the 7 types of operating system?
What are the 5 types of computer generation?
Last Updated: May 1, 2024

Generation of Operating Systems

Roadmap to SDE career at Amazon
Anubhav Sinha
SDE-2 @
25 Jun, 2024 @ 01:30 PM


An operating system (OS) is a collection of software that manages the hardware resources of a computer and provides a platform for running applications. It serves as an intermediary between the computer's hardware and the software that runs on it, providing a set of services and functions that enable applications to interact with the hardware.  

Generation of Operating Systems

The system program which acts as an interface between the user and the computing system is called the operating system. The user is able to run any program and communicate with the software applications in an easy and organized manner. The operating system is a system program that controls and manages the proper execution of application programs, software and hardware resources. 

Operating System Generations

The evolution of operating systems can be divided into four generations. 

Operating System Generations
  • First Generation (19405s-1955s): The first generation had no OS; tasks required manual setup. The first operating system was GM-NAA I/O which was used for real work. It was produced by General Motors' Research division in 1956 for its IBM 704. In the early days of IBM mainframes, customers were the developers of operating systems.
  • Second generation (1955s-1965s): The second generation introduced simple Batch Systems, automating tasks with job control languages.
  • Third-generation (1965s-1980s): The third generation brought time-sharing and multi-programming, enhancing resource sharing and efficiency.
  • Fourth generation (1980s-present): The fourth generation includes modern OS with graphical user interfaces, multitasking, and networking capabilities, providing user-friendly, powerful computing experiences.

First Generation ( 1945 - 1955 ): Vacuum Tubes and Plugboards

The first generation of the operating systems took place around 1945-1955 when the second world was happening. During the Second World War, there were no digital computers. Calculating engines that used mechanical relays were built at that time and were popularly used. These mechanical relays were extremely slow and were later on replaced by comparatively faster vacuum tubes. These machines took a large amount of space as they were enormous but were very slow.

Such types of computers were designed and built by a single group of people. At that time, programming languages were unknown, and there was no such thing as an operating system because of which all the programming was done in machine languages. Most of the problems which were solved using them were simple numerical calculations.

Punch cards were introduced in the 1950s, and they improved the overall computer system. Now instead of using plugboards, programs were written on cards and were handed to the operator, who fed them to the system.

Second Generation ( 1955 - 1965 ): Transistors and Batch Systems

The second generation of the operating systems took place around 1955 to 1965. The first operating system, GMOs was created in the early 1950s. General Motors developed this OS for the IBM computers.

In this period, transistors were developed, which led to the development of computer systems that could be manufactured and sold to paying customers. Such types of machines were known as mainframes. They were kept in air-conditioned rooms with trained staff to operate them.

Later, Batch systems were introduced in this generation of operating systems to reduce the computer's idle time. All the jobs were collected on a tray in the input room and were read into the magnetic tape. Then, the tape was mounted onto a tape drive once it had been rewound. When the batch operating system was loaded, it read the first job from the tape and ran it, while the output was written onto the second tape. After executing the whole batch, the input and output tapes were removed while the output tape was printed.

Third Generation ( 1965 - 1980 ): Integrated Circuits and Multiprogramming

The third generation of operating systems took place around 1965-1980. Initially, there were two types of computers - the scientific and commercial computers. Each type of computer served a different purpose. These were combined into one by IBM, which was known as the System/360. They used integrated circuits and offered a major price and performance advantage over the second-generation systems.

By the late 1960s, operating systems designers were capable of developing an operating system that was capable of performing multiple tasks simultaneously in a single computer. Such operating systems were known as multiprogramming operating systems. The introduction of multiprogramming played an important role in developing operating systems that allowed the CPU to be busy all the time by performing different tasks on a single computer simultaneously.

Fourth Generation ( 1980 - Present ): Personal Computers

The fourth generation of the operating system took place around 1980 and is being used till now. This generation of operating systems is related to the development of personal computers, which is very similar to the minicomputers that were developed in the third generation. Initially, the cost of personal computers was very high. The birth of Microsoft and windows operating systems played a major role in the development of personal computers. In this generation of operating systems, Microsoft created the first window operating system in 1975. After introducing the Microsoft Windows operating system, Bill Gates and Paul Allen had the vision to take personal computers to the next level. They introduced MS-DOS in 1981, tho it was very difficult for the person to understand its commands. After that, multiple operating systems were released by windows, such as Windows 95, Windows 98, Windows XP, etc. Currently, most Windows users use the Windows 10 operating system. Apart from windows, Apple also built an operating system in the 1980s, which is known as Macintosh OS. it was developed by Steve Jobs, co-founder of Apple.

Get the tech career you deserve, faster!
Connect with our expert counsellors to understand how to hack your way to success
User rating 4.7/5
1:1 doubt support
95% placement record
Akash Pal
Senior Software Engineer
326% Hike After Job Bootcamp
Himanshu Gusain
Programmer Analyst
32 LPA After Job Bootcamp
After Job

What is the Generation of Operating Systems?

The generations of operating systems refer to the historical development and evolution of operating systems over time. 

Types of Operating System

Let's discuss the types of approaches used to design operating systems for different kinds of users:

  • Single User Operating System: Designed for individual users. It is typically found on personal computers. It provides a simple interference and allows one user to perform tasks simultaneously—for example, macOS or Microsoft Windows.
  • Multi-User Operating System: It supports multiple users simultaneously, often on servers or mainframes. It enables concurrent access and resource sharing among users—for example, Linux and Unix.
  • Real-Time Operating System: It is used in applications requiring immediate response without delays. It ensures that time-critical processes are completed on time—for example, VxWorks, QNX.
  • Distributed Operating System: It runs on multiple interconnected machines to form a network. It facilitates communication and resource sharing across the web—for Example, Google's Chrome OS and Amoeba.
  • Time-Sharing Operating System: It allows multiple users to share system resources simultaneously. It divides CPU time into small time slices for each user—for example, CTSS and Multics.
  • Network Operating System: It is designed to manage and coordinate network resources and services. It facilitates file sharing, printing, and communication within a network—for example, Windows Server and Novell NetWare.

Frequently Asked Questions

Which OS is used in 4th generation?

The fourth generation of operating systems (1971-1980) saw the development of personal computer OS, such as CP/M and Apple DOS, and the introduction of microprocessors and more user-friendly interfaces. These OS made personal computing accessible and set the stage for future advancements.

How does the OS generation evolve?

OS generation has evolved to meet the changing needs of users. It started with manual setups, then automated batch systems made things easier. Later, time-sharing and multi-programming enhanced resource use. Now, modern OS with GUIs and multitasking offer user-friendly experiences.

What is the generation of operating system?

The generation of an operating system refers to its evolutionary stage or version. Each generation typically represents advancements in technology, features, and functionality, leading to improved performance and user experience.

What is the 5th generation operating system?

The 5th generation operating system, often associated with the late 1980s and early 1990s, focused on incorporating artificial intelligence (AI) and natural language processing capabilities. These systems aimed to provide more intuitive and user-friendly interactions with computers.

What are the 7 types of operating system?

The seven types of operating systems are:

  1. Batch Operating System
  2. Time-Sharing Operating System
  3. Distributed Operating System
  4. Network Operating System
  5. Real-Time Operating System
  6. Mobile Operating System
  7. Embedded Operating System

Each type serves specific purposes and caters to different computing environments and requirements.

What are the 5 types of computer generation?

The five types of computer generation are:

  1. First Generation: Vacuum tube computers
  2. Second Generation: Transistor-based computers
  3. Third Generation: Integrated circuit-based computers
  4. Fourth Generation: Microprocessor-based computers
  5. Fifth Generation: AI-based computers, emphasizing parallel processing and natural language understanding.


In this article, we have discussed the generation of operating systems. The evolution of operating systems reflects the continual progression of computing technology, with each generation bringing new capabilities and functionalities. From the early batch processing systems to the sophisticated AI-driven interfaces of today, operating systems have played a pivotal role in shaping the way we interact with computers.

Recommended Readings:

Do upvote our blogs if you find them helpful and engaging!

Happy Learning!

Previous article
Difference between System Software and Application Software
Next article
Difference between User Mode and Kernel Mode
Live masterclass