New to Open Source
So what is open source software? Source code is the human-authored text that, when interpreted by a computer, becomes software. There are two schools of thought in the software market today. One called proprietary software thinks of software like most people think of physical things you can buy like cars, toasters, and building supplies - goods that are subject to the economics of scarcity: if you sell me your surf board, I have it, and you don't.
The second, open source software is quite different. It recognises that, unlike physical goods, software is like an idea. It can be exchanged quite freely, and if I give you my idea, you have it too, but so do I. As with other forms of readily replicable data, the economic law of scarcity doesn't naturally apply to software.
Adherents to the proprietary software mentality use governmental and legal constructs like contracts (embodied in proprietary End User License Agreements or EULAs), and government granted monopolies like patents and copyright to restrict the natural copying of software - to restrict the freedoms of software users, to create an "artificial scarcity".
Proponents of open source software on the other hand, while respecting the rights claimed by proprietary software sellers, see these artificial proprietary limitations as neither desirable nor beneficial to the marketplace. They disagree with the basic tenant of proprietary software business models that software innovation only arises when the producers of that software can demand "monopoly rents" on the software through government granted intellectual monopolies.
Open source software uses the legal construct of copyright in exactly the opposite way to proprietary software. Rather than guaranteeing a monopoly to the copyright holder, open source software developers use copyright and a series of specially crafted licenses to guarantee, under various circumstances depending on the license used (managed by the Open Source Initiative), that no monopoly can be created with that software. The concept of "free software" is a special case of open source software, which is software licensed under the brilliant GNU General Public License (GPL). The GNU GPL guarantees 4 specific freedoms in perpetuity. Other open source licenses typically offer slightly lesser guarantees of perpetual freedom for various reasons.
The underlying principle of open source is "share and share alike". Open source software adherents assert that better software will ultimately result from the ability to build on the innovation of others - just as is enshrined in the "scientific method" that has governed scientific endeavour for thousands of years: scientists the world over in their search of a true understanding of our world have published their work for all to see. In doing so, they allow their peers to test and build on their ideas.
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