1. Manual operation (no operating system): The first computer was born in 1946 - in the mid-1950s, there was no operating system and manual operation was used for computer work.

Two characteristics of manual operation:

(1) The user has exclusive control of the entire machine. There will be no waiting due to resources being occupied by other users, but resource utilization is low.

(2)CPU is waiting for manual operation. The CPU is not fully utilized.

2. Batch processing system: A system software loaded on the computer. Under its control, the computer can automatically and batch process the jobs of one or more users (this job includes programs, data and commands).

Online batch processing system: The first to appear is the online batch processing system, that is, the input/output of the job is processed by the CPU.

Offline batch processing system: In order to overcome and alleviate the contradiction between high-speed host and slow peripherals and improve CPU utilization, an offline batch processing system is introduced, that is, the input/output is separated from the host control .

3. Multiprogramming system

Multiprogramming technology

The so-called multiprogramming technology refers to allowing multiple programs to enter the memory and run at the same time . That is, multiple programs are put into memory at the same time and allowed to run alternately in the CPU. They share various hardware and software resources in the system. When a program is suspended due to an I/O request, the CPU immediately switches to running another program.

Multi-channel batch processing system

In the mid-1960s, in the aforementioned batch processing system, multi-channel programming technology was introduced to form a multi-channel batch processing system (referred to as: batch processing system). processing system).

4. Time-sharing system

Due to the continuous improvement of CPU speed and the adoption of time-sharing technology, a computer can be connected to multiple user terminals at the same time, and each user can connect to multiple user terminals at the same time. Use the computer online like a dedicated machine (multi-user time-sharing systems are the most commonly used type of operating system in today's computer operating systems).

5. Real-time system: Real-time system is often used as a control device in a specific application.

6. General operating system

There are three basic types of operating systems: multi-channel batch processing system, time-sharing system, and real-time system.

7. Further development of operating systems

In the 1980s, the rapid development of large-scale integrated circuit technology and the emergence and development of microprocessors set off a great development of computers. A wave of great popularity. On the one hand, it ushered in the era of personal computers, and at the same time, it developed towards computer networks, distributed processing, supercomputers and intelligence. As a result, operating systems have further developed, such as: personal computer operating systems, network operating systems, distributed operating systems, etc.