How much do you know about Linux?
Introduction to Linux System
The Linux system is a multi-user, multi-task, multi-thread and multi-CPU operating system based on POSIX and UNIX. It was born on October 5, 1991 (the first time it was officially announced). It can run major UNIX tools, applications, and network protocols. Linux supports 32-bit and 64-bit hardware. Linux inherits Unix's network-centric design philosophy and is a multi-user network operating system with stable performance.
With the help of the Internet and the joint efforts of computer enthusiasts around the world, it has become the most used UNIX operating system in the world today, and the number of users is still growing rapidly.
Advantages of Linux system
Open source means that the system follows the world standard specifications, especially the Open System Interconnection (OSI) international standard. All hardware and software developed in accordance with international standards are compatible with each other and can be easily interconnected.
Multi-user means that system resources can be used by different users, and each user has specific permissions for his own resources (for example, files, devices) and does not affect each other. Both Linux and Unix have multi-user features.
Multitasking is one of the most important features of modern computers. It means that the computer executes multiple programs at the same time, and each program runs independently of each other. The Linux system schedules every process to access the microprocessor equally. Since the processing speed of the CPU is very fast, the result is that the launched applications appear to be running in parallel. In fact, there is only a short time delay between the processor executing a set of instructions in an application program and the Linux dispatching the microprocessor to run the program again, which the user can't feel.
4.Good user interface
Linux provides users with two interfaces: user interface and system call interface. The traditional user interface of Linux is a text-based command line interface, the shell. It can be used either online or offline. Shell has strong programming ability, users can use it to compile programs conveniently, thus providing more advanced means for users to expand system functions. Programmable Shell refers to the combination of multiple commands to form a Shell program. This program can be run alone or simultaneously with other programs.
The system call provides the user with an interface for programming. Users can directly use the system call commands provided by the system during programming. The system provides low-level and high-efficiency services for user programs through this interface.
Linux also provides a graphical user interface for users. It uses mouse, menu, window, scroll bar and other facilities to present a user-friendly graphical interface that is intuitive, easy to operate, and highly interactive.
Device independence means that the operating system treats all external devices as files. As long as their drivers are installed, any user can manipulate and use these devices just like files without knowing their specific existence.
An operating system with device independence simplifies the work of adding new devices by treating each peripheral device as an independent file. When a new device needs to be added, the system administrator adds the necessary connections in the kernel. This connection (also called a device driver) guarantees that every time a device is called to provide services, the kernel handles them in the same way. When new and better peripherals are developed and delivered to users, operations allow these devices to be accessed immediately without restrictions after they are connected to the kernel. The key to device independence is the adaptability of the kernel. Other operating systems only allow a certain number or types of external devices to connect. The device-independent operating system can accommodate any type and number of devices, because each device is independently accessed through its dedicated connection with the kernel.
Linux is an operating system with device independence. Its kernel is highly adaptable. As more programmers join Linux programming, more hardware devices will be added to various Linux kernels and distributions. In addition, since users can get the Linux kernel source code for free, users can modify the kernel source code to adapt to newly added external devices.
The difference between linux system and windows
Linux is a Unix-like operating system, which is more stable, safer (without anti-virus software), and efficient than windows. The current supercomputers basically use the Linux system. His application is relatively complete, but most software developers did not give due attention, which is related to the short development history of Linux. With the continuous development of Linux, there will be more and better software.
At the same time, we must realize that the Linux system is different from windows. We are accustomed to windows and it is difficult to get used to the operation of the linux system. Now the better-used Linux are ubuntu, fedora, debian, mint, opensuse and so on.