Freedoms 1 and 3 require source code to be available because studying and modifying software without its source code is highly impractical.
What is it?<br />History?<br />How it evolved?<br />Free Software Today.<br />Free Software<br />
Free software, software libre or libre software issoftware that can be used, studied, and modified without restriction, and which can be copied and redistributed in modified or unmodified form either without restriction, or with minimal restrictions only to ensure that further recipients can also do these things and that manufacturers of consumer-facing hardware allow user modifications to their hardware. Free software is generally available without charge.<br /> <br />In short it is software that anyone may run, share, and change, at any time, for any reason.<br />What is Free Software?<br />
In the 1950s, 1960s, and 1970s, it was normal for computer users to have the freedoms that are provided by free software. Software was commonly shared by individuals who used computers and by hardware manufacturers who were glad that people were making software that made their hardware useful.<br />While some software might have always remained free, there was a growing amount of software that was for sale only. In the 1970s and early 1980s, the software industry began using technical measures (such as only distributing binary copies of computer programs) to prevent computer users from being able to study and modify software. In 1980 copyright law was extended to computer programs.<br />History<br />
In 1983, Richard Stallman, longtime member of the hacker community at the MIT Artificial Intelligence Laboratory, announced the GNU Project, saying that he had become frustrated with the effects of the change in culture of the computer industry and its users. Software development for the GNU Operating System began in January 1984, and the Free Software Foundation (FSF) was founded in October 1985. He developed a free software definition and the concept of "copyleft”, designed to ensure software freedom for all.<br />Evolution<br />
Evolution-Continued<br />The first formal definition of free software was published by FSF in February 1986. That definition, written by Richard Stallman, is still maintained today and states that software is free software if people who receive a copy of the software have the following four freedoms:<br />Freedom 0: The freedom to run the program for any purpose.<br />Freedom 1: The freedom to study how the program works, and change it to make it do what you wish.<br />Freedom 2: The freedom to redistribute copies so you can help your neighbor.<br />Freedom 3: The freedom to improve the program, and release your improvements (and modified versions in general) to the public, so that the whole community benefits.<br />
Thus, free software means that computer users have the freedom to cooperate with whom they choose, and to control the software they use. To summarize this Richard Stallman said: "Free software is a matter of liberty, not price. To understand the concept, you should think of 'free' as in ‘free speech’, not as in ‘free beer’<br />Evolution-Final<br />