1. What is open source software
Open source software is software whose source code is made public under an open source agreement and allows others to use, learn, modify, and distribute in any form.
2. A brief history of open source software
1950s and 1960s-the first open source software
In the 1950s and 1960s, most of the software was written by researchers in academia and enterprises in cooperation. These softwares were shared in the form of Public-Domain Software, that is, Today we call open source software. The sharing of these software adheres to the principles of openness and cooperation in the academic world, and has not been commercialized. At that time, the compatibility of different hardware and operating systems was not good, so the source code of the software was released together with the machine code to facilitate modification and modulation.
It is currently recognized that the earliest open source software is the A-2 system in 1953, the second version after the A-0 system. So what is the A-0 system? A-0 System (A-0 System), full name Arithmetic Language Version 0, is the compiler on the first commercial electronic computer UNIVAC I, which can compile programs into machine code.
It was developed between 1951 and 1952 by the United States Commodore and Grace Hopper, one of the first female computer scientists. Later, in 1953, after the early American computer manufacturer, Remington Rand Corporation, developed the A-2 system, the source code was released to the majority of users, and users are welcome to submit improvements to the A-2 system.
Since then, almost all of IBM's mainframe computers have been released with the source code. Some universities even explicitly stipulate that all software installed on computers must have open source code.
From the end of the sixties to the beginning of the seventies-the number of open source software began to decrease
However, after the late 1960s, with the evolution of operating systems and compilers, the cost of manufacturing software has increased relative to hardware. The software industry gradually developed and began to compete with the software released by the hardware manufacturers at that time. Bundled open source software has gradually become "pleasant and thankless", because although the software is nominally open source, the cost of development is still added to the price of the overall machine, but some consumers do not want to bundle it for personalized needs. Pay for the software. On January 17, 1969, the US government even accused the bundled software of anti-competitive behavior in a legal action between the United States and IBM. Although some software was still free at the time, more and more software began to be commercially sold under restrictive licenses.
In the beginning, software was not protected by copyright. Until 1974, the US Commission on New Technological Uses of Copyrighted Works decided that computer programs were also personal originals and should be granted corresponding legal copyrights. Since then, those unlicensed software will be shared with the public as public domain software along with the source code.
From the end of the seventies to the beginning of the eighties
From the late 1970s to the early 1980s, computer vendors and software companies began routinely charging for software licenses, treating new software development as company property, and imposing legal restrictions in the form of copyrights, trademarks, and lease contracts. In 1976, Bill Gates also wrote an article, "An Open Letter to Hobbyists" (An Open Letter to Hobbyists). In the article, Gates said that hobbyists shared a lot of the Microsoft product Altaire without paying a license fee. BASIC (a compiler for the BASIC language), he was very disappointed with this and thought it was unfair to the developer's time and effort. In order to increase profits, companies generally no longer release source code, but only release executable, compiled machine code.
The famous American programmer and free software activist, Richard Stallman (Richard Stallman), expressed frustration at this phenomenon. He worried that he would no longer be able to learn or modify software written by other people from now on. He even thinks that the behavior of large companies to retain source code is an ethical error. Therefore, in 1983, he launched the famous GNU project at MIT, a free software collective collaboration project, with the purpose of developing a completely free (Free Software) operating system. He also issued the "GNU Manifesto", explaining the original intention of launching this plan. One of the reasons was to "reproduce the solidarity of cooperation and mutual assistance in the software industry."
It should be particularly emphasized here that many people now regard Open Source Software and Free Software as synonyms, but there are still differences between the two. Stallman explained in the article "Why open source misses the key points of free software":
"The two terms describe almost the same category of software, but they stand for views based on fundamentally different values. Open source is a development methodology; free software is a social movement. "
"These two terms describe almost the same category of software , But it shows two different value angles. Open source is a software development methodology, and free software is a social movement.
However, open source and free software are not conceptually conflicting. Therefore, we will put Both are regarded as synonyms.
80s to 90s
After Stallman founded the GNU project , many of GNU's products have been widely used, such as the GNU debugger and Emacs document editor. In addition to GNU's free software project, there are also many informal software sharing at the same time. For example, so-called hobbyists and hackers will share code through computer magazines and computer books before the Internet is widely used. Later, with the popularization of the Internet, many programmers also shared the source code on the electronic bulletin board system (abbreviated as BBS in English, which is the predecessor of the current popular online forum).
In the 1990s, the development of the Linux kernel was in perfect harmony with the GNU operating system lacking only the kernel. GNU/Linux became the first completely free and open source operating system , and it has been used by programmers to this day. At present, many people directly omit "GNU" and call this operating system Linux. In fact, Stallman is quite dissatisfied with this title. He insists that it should be called "GNU Linux" to reflect the common contributions of GNU and Linux.
In the early 1990s, more open source operating systems were released, such as FreeBSD and NetBSD, which, like GNU/Linux, are also Unix-like operating systems. FreeBSD and NetBSD are based on the BSD system (the full name is Berkeley Software Distribution, translated as Berkeley software package, created by Bill Joy, a student at the University of California, Bokeley). (Since then, in 1995, OpenBSD was developed based on NetBSD; in 2004, Dragonfly BSD was developed based on FreeBSD.)
Late nineties to present
In 1998, Eric Raymond and Bruce Perens established the Open Source Initiative (OSI, Chinese name "Open Source Promotion Association"), and began to provide open source code to commercial enterprises (such as Netscape). OSI believes that free open source code will bring more practical benefits than closed source code, and hopes that software giants and other high-tech companies can also turn to open source.
Nowadays, with the popularization of personal devices and technologies, countless high-quality open source software and projects have sprung up, ranging from browsers and operating systems to various programming languages, compilers, enterprise management tools, games...
supplement
1) What is the relationship between GNU and Linux?
After the Unix system was invented, everyone used it very well. But then began to charge and commercial closed source. Richard Stallman was very upset about this, so he initiated the GNU project to imitate the interface and usage of Unix and make an open source version from scratch. Then he made his own editor Emacs and compiler GCC. GNU is a project or movement. Under this banner, FSF was established and GPL was drafted. After that, everyone did a lot of work and projects under the GNU plan, and basically realized the original plan. Including the core gcc and glibc. But the GNU system lacks the operating system kernel. The original kernel is called HURD, and it has not been completed. At the same time, BSD (a UNIX distribution) was caught in a copyright dispute, and the development of the x86 platform was suspended. Then a classmate named Linus developed Linux under the inspiration of Minix in order to run Unix on the PC. Note that Linux is only a system kernel , and software such as gcc and bash are still used after the system is started. Linus chose the GPL when releasing Linux, so it conforms to the principles of GNU. Finally, everyone suddenly discovered that this thing happened to be missing from the GNU project. So they are packaged and released together and called GNU/Linux. Then everyone thought about it and omitted the previous part and became a Linux system. In fact, the kernel occupies only a small part of the capacity in Linux distributions such as Debian and RedHat.
2) What is GNU?
GNU is a free operating system, and its content software is completely released under GPL. This operating system is the main goal of the GNU project. The name comes from the recursive acronym of GNU's Not Unix!, because GNU is designed like Unix, but it does not contain copyrighted Unix code. The founder of GNU, Richard Matthew Stallman, regarded GNU as a "technical method of achieving social goals."
As an operating system, the development of GNU has not yet been completed. The biggest problem is that a fully functional kernel has not been successfully developed. The GNU kernel, called Hurd, is the focus of the development of the Free Software Foundation, but its development is not yet mature. In actual use, most alternatives such as the Linux kernel and FreeBSD are used as the core of the system. The main operating system is the Linux distribution. The Linux operating system contains the GNU components and software in the Linux kernel and other free software projects. It can be called GNU/Linux, but this naming has always been controversial.
The GNU/Linux naming dispute is a dispute arising in the free software community regarding the name of the Linux operating system.
The founder of the Free Software Foundation, Richard Stallman, and its supporters, proposed the name GNU/Linux, hoping to use it as the official name of the Linux operating system. These people think that the Linux operating system, including the GNU project software and the Linux core, uses the name GNU/Linux to well summarize its content. Moreover, the GNU project originally took the development of an operating system as a remote plan, but it has not been completed. The Linux operating system can just fill this gap.
Members of the Linux community believe that the name Linux is more common among the public and the media, and put forward several reasons, believing that it is better to use the Linux name.