Include third-party works with caution, as you could accidentally infringe someone's copyright otherwise. Whenever you are unsure if you could use others' work or not, exclude it from your article or find an alternative.
There is no universal ruling on copyright. Instead, each country has its own laws on the matter. The wiki is open to the whole world — meaning that we should try to satisfy even the strictest jurisdiction.
The copyright information is usually provided with the source. If it is not there, assume that you cannot use that source.
Permissive Licenses and Public Domain
Works in public domain are not protected by copyright — anyone can use them. A work can fall into public domain if the author is long dead, if the author waives the copyright or it is taken away by the court, or if the nature of the work does not allow copyright to begin with.
All jurisdictions limit copyright by the age of a work, but the exact age varies. Most countries limit it to 50 to 70 years after the death of author, but some extend it further. It takes the longest in Mexico. There, copyright expires one hundred years after the death of author. Use the Mexican ruling to determine the status of a work.
Sometimes authors waive their copyright. In some jurisdictions, they simply have to express their will. Some others consider author's rights so natural so even the author cannot refuse them. An alternative to public domain is a functionally equivalent license: namely, CC0 or Unlicense. For practical purposes, treat such licenses the same as public domain.
Be careful. Derived works can still be protected by copyright, and the line is not that obvious sometimes. For example, Vincent van Gogh's letters are in public domain, but their translations by vangoghonline.com are not.
You can use any work under the MIT license or CC BY — but not CC licenses with NC, ND, or SA postfixes. Attribution is legally required.
Right To Quote and Fair Practice
The most of the world has accepted the Berne Convention for the Protection of Literary and Artistic Works. In Article 10, it states:
(1) It shall be permissible to make quotations from a work which has already been lawfully made available to the public, provided that their making is compatible with fair practice, and their extent does not exceed that justified by the purpose, including quotations from newspaper articles and periodicals in the form of press summaries.
This overrides copyrights — meaning that you can quote others or include parts of their work. You must treat the source and the author fairly, but different countries have different definition of fair practice. Follow the strictest guideline:
- The purpose of derived work: you can quote for educational or research purposes, but typically not for advertisement.
- Usage: Quote only to support your point. For example, do not put someone's painting in a blog post just so it would look prettier.
- Amount: Quote just enough to support your point.
- Necessity: Consider if there are alternative sources that are not protected by copyright.
- Business interests: Do not quote something if it can conflict with the owner's business. For example, you can hurt the sales of a fresh book if you publish the last page.
- Ethics and morals: You are allowed to criticize. However, you must never attack the author's honor or reputation. Never express or imply that the usage is endorsed by the source's author.
You must attribute the author and the source.
Always attribute the author even if it is not legally required. State the author's name and the source. Provide link to the source, if possible. Mention the license if applicable and provide link to its text. If you have modified the work anyhow, mention that, too.
Also see the Formatting reference.
Contribute only your original work. Always make it clear where you include others' work and who is the original author.
If you copy whole sentences or paragraphs you are plagiarizing word-for-word. Copying separate phrases is mosaic plagiarism, and rewriting the source while you keep the author's reasoning is paraphrasing — yet another form of plagiarism. The best way you could avoid plagiarizing is to read the source to learn about the subject — and then explain it not just in your own words, but in your own understanding.
Materials From the IOTA Wiki
If you cite IOTA Wiki within IOTA Wiki, just leave the link to the source article instead of full attribution.