Creative Commons licenses establish a legal framework that makes it easier for authors to decide how their works are to be distributed and used by third parties.

When the author grants a Creative Commons license to his work, he does not waive his rights, but authorizes its use under certain conditions:

• Attribution: it is necessary to recognize authorship in any exploitation of the work
• NonCommercial: the work is limited to non-commercial uses
• NoDerivatives: transformation is not allowed to create a derivative work
• ShareAlike: the creation of drift works is authorized provided that the same license is granted to them

From the combination of these conditions, six types of Creative Commons licenses can be generated:

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  Attribution (CC BY): It allows any type of exploitation, including its use for commercial purposes and the creation of derivative works, provided that the authorship of the original work is recognized. It is the least restrictive of all licenses and recommended for maximum dissemination.
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  Attribution-ShareAlike (CC BY-SA): allows any type of exploitation and generation of works derived from the original to be made, even for commercial purposes, provided that authorship is recognized and a license is attributed to the derivative work under the same terms as the original.
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  Attribution-NoDerivs (CC BY-ND): It allows the use of the work, even for commercial purposes, provided that authorship is recognized and no adaptations are made or derivative works are generated.
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  Attribution-NonCommercial (CC BY-NC): It allows you to use the original work and generate derivative works, provided that a commercial purpose is not pursued and the authorship of the first is recognized.
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  Attribution-NonCommercial-ShareAlike (CC BY-NC-SA): It allows to use the original work and generate other derivatives of it, without commercial purposes, as long as the authorship is recognized and the new creations are licensed in the same terms as the original.
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  Attribution-NonCommercial-NoDerivs (CC BY-NC-ND): It is only allowed to use the work recognizing its authorship but without modification or generation of new works from the original and without commercial purposes. It is the most restrictive of the six licenses.

As the copyright owner, you can decide which license you want to grant to your work, that is, what are the uses allowed to third parties based on conditions. When depositing a job in the repository, you must choose the Creative Commons license mode that you want to apply. Otherwise, the CC BY-NC (Attribution-NonCommercial) modality will be applied, which is the default license of the Institutional Repository of the Regional Health System of the Community of Madrid.

Creative Commons licenses are valid worldwide. In addition, being based on intellectual property laws, their duration is equal to the duration of copyright.