Linux introduction (Good!) ）

Linux Operating system Introduction

Source: 233 Essay Center [2009-12-02 14:23:00] read: 1 Wangchangqing edit: studa20

"Abstract" from the generation of UNIX and Minix system, the Linux operating system is introduced, the generation process of Linux operating system is described in detail, the network market-based development mode of Linux is analyzed, and the main features and functions of Linux are analyzed and introduced by studying the development process of Linux.

"keywords" Linux operating system network operating system kernel

First, the generation of Linux

Linux is a computer operating system, often referred to as a Unix-like system, because Linux and Unix have deep roots.

In a very expensive computer era, only in universities or large enterprises to access the computer, people very much want to be able to connect to a computer at the same time and use it. As a result, computer scientists began to study time-sharing systems. The time-sharing system is divided into a small time slice of the CPU runtime, and multiple user tasks can be used to quickly interact with the CPU by alternating time slices. Because time slices are a short period of time, each user task, each user seems to monopolize the CPU and monopolize the entire computer system. With the tireless efforts of researchers, the UNIX system was developed in 1969 at the T-Bell Laboratory.

In 1986, Professor Andrew Tanenbaum of the University of Helsinki in Finland developed the MINIX system, a variant of UNIX, to teach students the computer operating system course. In 1991, Professor Andrew Tanenbaum's student Linus Torvalds, who was less satisfied with the Minix system used in the classroom, began trying to improve the 386 system on the Minix pc.

In August 1991, Linus Torvalds posted the following phrase in Comp.os.minix newsgroups: "Hello, everyone who uses minix, I am doing a free operating system for 386 (486) at, just for hobby, ..." Linus originally named his own system Freax, he put the source code in a Finnish FTP site for everyone to download. The administrator of the site thought the system was a Linus Minix system, so a folder called Linux was created to store it. As a result, Linus's "hobby" has become today's Microsoft's number one opponent, the powerful and inexpensive Linux operating system.

At the end of 1993 at the beginning of 94, Linux 1.0 was finally born! Linux1.0 is already a full-featured operating system, and the kernel is written in a compact and efficient, can fully play the performance of the hardware, in 4 m memory of the 80386 machine is also very good, so far people are still relish this. Linux and is a name called, Linux is Linus Torvalds all. This is due to the fact that a lawyer named William R. Della Croce began sending letters to various Linux publishers stating that he owned Linux and asked publishers to pay royalties, which collectively appealed for the re-distribution of the registered trademark to Linus 　　 　　Torvalds. Second, the development model of Linux

Linus released the first Linux version of Linux 0.0.2 on October 5, 1991 and published the source code for the Linux core program on the Web, and decided to distribute it in the form of the GPL (public-owned copyright, also known as the Gun Common license). This means that the software allows anyone to modify and propagate in any form.

With the increasing popularity of the network, more and more skilled programmers are adding to the development and perfection of Linux. In the process, countless personality and pioneering programmers, without any compensation, are completely spontaneous in the development ranks. Once a programmer has completed some of these programs, he will immediately publish the program and send it to anyone who needs it for free, and some other programmers will revise and refine it after studying it and then publish it. 　　This process repeats itself, so the speed of Linux improvement is the fastest, and its stability is very high. So, Linux was not developed by Linus alone, but was developed by hundreds of programmers around the world, and of course Linus was toned for the kernel. This market-based development model has contributed to the prosperity of Linux systems. It can be said that Linux is completely a passionate, free, open network product.

Third, the development of Linux
　　
Linux has good compatibility and portability. Around the 1.3 release, Linux began porting to other hardware platforms, including the fastest cpu--digital Alpha. So do not always put Linux and low-end hardware platform to link to a piece, Linux is only the performance of the hardware fully play out. Linux will be swept from low-end applications to high-end applications!
To make Linux easy to use, Linux also has many release versions, and the release is actually a complete set of program combinations. Now that there are many different Linux distributions and their respective version numbers, for the sake of not confusing, let's first explain some of the commonly mentioned terms. When we refer to Linux, it is generally referred to as "Real Linux", the kernel, which is the "heart" of all Unix operating systems. But Linux does not have to be a usable operating system, but it also requires many packages, compilers, library files, Xwindow systems, and so on. Because of the different combinations, the user-oriented objects are different, so there are many different Linux distributions.
More and more companies are developing commercial software on Linux or porting software from other UNIX platforms to Linux. Today, many of the IT industry's big names IBM, Intel, Oracle, Infomix, Sysbase, Corel, Netscape, CA, Novell and so on have announced support for Linux. Merchants to join to make up for the lack of pure free software and development barriers, Linux quickly spread to the vast number of computer enthusiasts, and into commercial applications, to break the monopoly of certain companies in the cultural circle of hope.
Linux is a collaborative development of enthusiasts through the Internet, of course, its network function is very powerful. For example, you can install Linux through FTP, NFS, etc., and use it as a gateway and so on. With the development of Linux, the application of the derivation is probably not Linus I originally expected. If someone uses it to do the router, someone to do the embedded system, someone to do real-time system .... Shong asked what Linux can do? It's not like the operating system you don't use, it's not what you can do with it, but what you want to do.
Linux is a UNIX system that runs on a PC. The Linux system has all the latest UNIX features, including true multitasking, virtual storage, shared library functions, instant load, superior storage Management and TCP/IP, UUCP Network Tools, and more. Linux systems and their development are POSIX compliant, with kernels supporting Ethernet, PPP, SLIP, NFS, ax.25, Ipx/spx (Novell), NCP (Novell), and more. System applications include Tellnet, Rlogin, FTP, Mail, Gopher, talk, term, news (tin, trn, nn) and a full set of Unix toolkits. X graphics library, including Xterm, FVWM, Xxgdb, Mosaic, XV, GS, Xman and all other X-win application tools. Commercial software has motif, WordPerfect. Chinese tools have cxterm, Celvis, CEMASC, Cless, Hztty, Cytalk, Ctalk, Cmail, etc., can handle GB, BIG5, Hz files. In addition, there are DOS simulation software, you can run the software under the Dos/win.
At the beginning, Linux was a product of a personal passion. Now, however, Linux has become an operating system that has received widespread attention and support. and other commercially available UNIX systems, as well as Linux as free software, have the advantage of low cost, high security, and reliability. Until today, Linux has become a well-functioning mainstream network operating system.