This guide provides an overview of common open source licensing options, ranging from most restrictive (No License) to least restrictive (The Unlicense).
By default, all creative works (including software) are automatically protected by copyright law. Without explicitly choosing a license, others cannot legally use, modify, or distribute your code. This default protection may be more restrictive than intended - choosing an open source license (described below) allows others to use your code while maintaining your copyright.
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The most permissive option, dedicating your work to the public domain. Users can do anything with the code without any conditions - including using it in closed-source projects without attribution.
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A popular, simple license requiring only that users preserve copyright and license notices. Allows commercial use, modification, and distribution under any terms.
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A permissive license whose main conditions require preservation of copyright and license notices. Contributors provide an express grant of patent rights. Licensed works, modifications, and larger works may be distributed under different terms and without source code.
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A “weak” copyleft license requiring source code sharing for modified files only. Larger projects can use different licenses for new files. More Information
A copyleft license with patent rights protection and special termination clauses for patent litigation. Doesn’t require reciprocal licensing for linked works.
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A hybrid license allowing free use in many scenarios but requiring a commercial license for production use in business environments. Designed to balance open source principles with business sustainability.
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