Keywords Linux operating system; Network operating system; core
First, the emergence of Linux Linux is a computer operating system, which is usually called Unix-like system. This is because Linux and Unix have deep roots.
In the era when computers are expensive, computers can only be accessed in universities or large enterprises. It is very desirable that multiple users can connect to a computer and use it at the same time. So, computer scientists began to study time-sharing system. The time-sharing system divides the running time of CPU into small time slices, and multiple user tasks realize the rapid interactive use of CPU by alternately occupying time slices. Because the time slice is a short period of time, it seems that every user is monopolizing the CPU and the whole computer system. With the unremitting efforts of researchers, 1969, at & amp； Bell Laboratories of T Company developed Unix system.
From 65438 to 0986, Professor Andrew Tanenbaum of Helsinki University, Finland, developed a Unix variant Minix system in order to teach students the course of computer operating system. 199 1 year, Linus Torvalds, a student of Professor Andrew Tanenbaum, was not satisfied with the Minix system used in class, so he began to try to improve the Minix system on 386 PC.
199 1 August, Linus Torvalds posted the following words in the comp.os.minix news group: "Hello everyone who uses minix, I am making a free operating system for 386(486)AT, just out of hobby, ..."
Linus originally named his system freax, and he put the source code on an FTP site in Finland for everyone to download. The administrator of this site thinks this system is Linus Minix system, so a folder named Linux is established to store it. As a result, Linus's "hobby" has become Microsoft's number one rival, a powerful and cheap Linux operating system.
1at the end of 993 and the beginning of 94, Linux 1.0 was finally born!
Linux 1.0 is already a fully functional operating system with a compact and efficient kernel, which can give full play to the performance of hardware. It also performed well on the 80386 computer with 4M memory, and it is still being discussed.
The sum of Linux is called, and the sum of Linux belongs to Linus Torvalds. This is because at present, a lawyer named William R. Della Croce has started to send letters to various Linux publishers, stating that he owns the ownership of Linux and asking them to pay royalties. These publishers collectively called for the redistribution of registered trademarks to Linus Torvalds.
Second, the development mode of Linux Linus released the first version of Linux, Linux 0.0.2, on 199 10 June 5, and released the source code of the Linux core program on the Internet, and decided to release it in the form of GPL (public copyright, also known as GUN General License), that is to say, this software allows anyone.
With the increasing popularity of the Internet, more and more highly skilled programmers have joined the development and improvement of Linux. In this process, countless creative programmers spontaneously joined the ranks of development without any reward. Once a programmer has finished some of these programs, he will immediately release the program and send it to anyone who needs it for free. Other programmers will revise and improve it after research, and then publish it. This process goes on and on, so Linux has the fastest upgrade speed and high stability.
So Linux was not developed by Linus alone, but by hundreds of programmers all over the world. Of course, Linus set the tone for internal verification. This market-oriented development model has contributed to the prosperity of Linux system. It can be said that Linux is a passionate, free and open network product.
Third, the development of Linux Linux has good compatibility and portability. After 1.3 version, Linux began to be transplanted to other hardware platforms, including CPU, the fastest CPU Digital Alpha. So don't always associate Linux with low-end hardware platforms. Linux only gives full play to the performance of hardware. Linux will definitely sweep from low-end applications to high-end applications!
In order to make Linux easy to use, Linux also has many release versions, which are actually a complete set of programs. There are many different Linux distributions and their version numbers. To avoid confusion, let's explain some common terms first. When we talk about Linux, we generally mean "real Linux", that is, the kernel, which is the "heart" of all UNIX operating systems. But linux alone can't be an available operating system, and many software packages are needed, such as compilers, library files, Xwindow systems and so on. There are many different Linux distributions due to different combinations and different user-oriented objects.
More and more companies develop commercial software on Linux, or transplant software from other Unix platforms to Linux. Now many IT giants such as IBM, Intel, Oracle, Infomix, Sysbase, Corel, Netscape, CA, Novell, etc. Support for Linux has been announced. The participation of merchants makes up for the shortcomings and obstacles of pure free software. Linux has rapidly spread to the vast number of computer enthusiasts and entered commercial applications, which has become the hope of breaking the monopoly cultural circle of some companies.
Linux is developed by enthusiasts through the Internet. Of course, its network function is very powerful. For example, you can install Linux through ftp and nfs and use it as a gateway. With the development of Linux, the derivative applications may have exceeded Linus' original expectations. If someone regards it as a router, someone regards it as an embedded system, and someone regards it as a real-time system ... Novices often ask what Linux can do? In fact, it is not like those ugly operating systems, not what you can do with it, but what you want to do.
Linux is a Unix system running on a PC. Linux system has all the functions of the latest Unix, including real multitasking, virtual storage, * * * library functions, real-time loading, superior storage management, TCP/IP, UUCP network tools and so on. Linux system and its development conform to Posix standard, and its kernel supports Ethernet, PPP, SLIP, NFS, AX.25, IPX/SPX(Novell), NCP(Novell) and so on. System applications include tellnet, rlogin, ftp, Mail, gopher, talk, $ term, news(tin, trn, nn) and other complete UNIX toolkits. X graphics library, including all X-Win application tools such as xterm, fvwm, xxgdb, mosaic, xv, gs, xman, etc. Commercial software includes Motif and WordPerfect. Chinese tools include Cxterm, celvis, cemasc, cless, hztty, cytalk, CCTALK, cmail, etc. , can handle GB, BIG5, HZ files. In addition, there is DOS simulation software, which can run under DOS/Win.
At first, Linux was just a product of personal passion. But now, Linux has become a widely concerned and supported operating system. Compared with other commercial Unix systems, Linux, as a free software, has the advantages of low cost, high security and strong reliability. Until today, Linux has become the mainstream network operating system with perfect functions.