There are several operating systems:

1. Windows operating system: Windows 3.1 was launched on July 27, 1993, a graphical operating system based on OS/2. And launched Windows 95 on August 15, 1995.

The Windows system at this time was still based on MS-DOS, but at the same time Microsoft was also developing NT series Windows systems that did not rely on DOS, and later completely abandoned DOS and turned to NT serves as the foundation of Windows.

The WINDOWS series operating system has an intuitive and efficient object-oriented graphical user interface, which is easy to learn and use, has a unified, friendly and beautiful user interface, rich device-independent graphical operations, and a multi-task operating environment. , is currently the most popular operating system.

2. Unix operating system: It is a powerful multi-user, multi-tasking operating system that supports multiple processor architectures. According to the classification of operating systems, it is a time-sharing operating system. It was first developed by Ken Thompson, Dennis Ritchie and Douglas McIlroy in 1969 at AT&T's Bell Labs.

UNIX systems are mostly written in C language, providing rich, carefully selected system calls, and providing a powerful programmable Shell language as the user interface, as well as a variety of communication mechanisms.

3. Linux operating system: In the 1990s, the open source operating system-Linux emerged. The Linux kernel is a standard POSIX kernel. In addition to its impressive portability (the source code can be modified at will), Linux is also a time-sharing multi-process kernel and has good memory space management (ordinary processes cannot access the memory in the kernel area). ).

The basic ideas of Linux are twofold: first, everything is a file; second, every software has a definite purpose.

4. Mac OS operating system: It is an operating system that runs on Apple's Macintosh series computers. Mac OS was the first commercially successful graphical user interface system.

5. Netware operating system: Netware is a network operating system launched by NOVELL. The most important feature of Netware is the open system structure based on basic module design ideas. Netware is an open network server platform that can be easily expanded.

6. MS-DOS operating system: Disk Operating System (DOS) is an early operating system, and WINDOWS was the graphical operating system application of this system in its early days. This operating system can combine any number of sectors, so any number and size of files can be placed on a disk, and the files are distinguished by file names.