A Detailed Look at Creative Commons Licenses
Quick Overview
What the license covers
Creative Commons (CC) is the most common license you will see on blogs.
It describes four core permissions:
Attribution (BY): copies must credit the original author.
NonCommercial (NC): the work may not be used for commercial purposes.
NoDerivatives (ND): the content cannot be modified when it is redistributed.
ShareAlike (SA): if you modify the work, you must license your version under the same CC terms.
These rights can be combined, but some combinations are not allowed (e.g., ND and SA conflict). In practice there are six options:
- Creative Commons Attribution (CC BY)
- Creative Commons Attribution-ShareAlike (CC BY-SA)
- Creative Commons Attribution-NonCommercial (CC BY-NC)
- Creative Commons Attribution-NoDerivatives (CC BY-ND)
- Creative Commons Attribution-NonCommercial-NoDerivatives (CC BY-NC-ND)
- Creative Commons Attribution-NonCommercial-ShareAlike (CC BY-NC-SA)
Which license should I choose?
The official chooser walks you through the decision with two questions:
- Do you allow derivative works? yes / no / yes but only under the same license
- Do you allow commercial use? yes / no
Answering these two questions determines the four permissions. Pick whatever matches your needs.
In Depth
Background
Creative Commons licenses come from the non-profit Creative Commons. They apply to creative works such as books, movies, music, blogs, and articles.
You own your work as soon as you create it, but how should others use it? Physical objects are easy—you lose them when someone takes them. Digital works like articles can be copied endlessly, so you need rules: perhaps no commercial use, and mandatory author credit. You could draft your own agreement, but that takes expertise. Creative Commons designed a set of ready-made licenses that spell out how others may use your work; you simply pick the one that fits.
The licenses have evolved—version 4.0 is the latest. Earlier versions required localized variants tailored to local laws. Version 4.0 discourages localization because the global text already factors in jurisdiction differences. See the references for more about CC 4.0 updates.
Three layers of expression
Creative Commons presents each license in three complementary forms:
- Machine-readable metadata: HTML snippets you embed on your site so browsers and search engines know which license you use.
- Human-readable summary: a plain-language explanation of the key terms—usually enough for most people.
- Legal code: the full legal text that defines every detail. Read this if you need to understand a specific clause.
Frequently asked questions
Creative Commons Mainland China publishes answers to common questions. I have adapted a few that come up often and added some of my own.
How does a CC license relate to copyright law?
Here I focus on the Copyright Law of the People’s Republic of China; other regions are similar.
A CC license operates within the framework of copyright law. Copyright law gives you ownership of the work and lets you grant certain permissions (see Article 24: users must obtain permission unless exceptions apply). It does not specify exactly what permissions to grant or under what conditions. A CC license is a standardized contract tailored to the online world that spells out those permissions.
What works does a CC license cover?
CC licenses apply to works protected by copyright: books, websites, blogs, photos, films, videos, songs, and other audio or video creations. Because software has its own specific concerns, CC recommends using dedicated open-source licenses instead of CC licenses for code.
What if I change my mind after licensing my work?
Creative Commons licenses are irrevocable. You cannot stop someone who already obtained your work under a CC license from continuing to use it within the license terms. You may stop offering the work under that license going forward, but you cannot pull back existing copies—whether they are verbatim copies, compilations, or derivative works. Think carefully before choosing a license if you might want to restrict usage later.
Can I remove attribution from derivatives or compilations?
If you dislike how someone reused your work under a CC license, you can ask to have your name removed from the derivative or compilation.
Does NonCommercial mean the work can never be used commercially?
Not necessarily. Choosing a NonCommercial clause means the CC license itself does not grant commercial rights. You can still negotiate a separate commercial license directly with the author.
References:
《Creative Commons license on Wikipedia》