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Copyright is a protection given to creators of intellectual works, such as books, music, and art. Copyright gives the creators of the works the right to make decisions about how their work can be used, including whether copies can be made and distributed, public performances of their work staged, and “derivative works” (works adapting or altering the original work) produced. It is often illegal for anyone to use another person’s work in any of these ways.

Copyright shows respect for the creators of these works. Ignoring copyright restrictions is copyright infringement. Two exceptions to copyright infringement are fair use and works in the public domain.


Not all use of another person’s work is considered to be copyright infringement. Fair use doctrine allows people to use copyrighted works under certain conditions. For example, using works for teaching, research, or criticism would typically fall under fair use and therefore be allowed under copyright laws. When determining if it is fair to use something, one must consider:

  • The nature of the use (if it is for nonprofit purposes, it is more likely to be fair use)
  • The nature of the work itself (factual information is more likely to fall under fair use than creative works)
  • The amount and the significance of the work to be used (using a small portion as opposed to a large portion of the work is more likely fair use)
  • The effect of using the work on the market (if the copyright owners will lose money by another person using their work, that would not be fair use)

If the use is fair, people may then use another person's creative work - but they should remember to cite the work properly. 


When using ideas from another person or organization, you must properly cite them. This means to properly identify where you found the information you are using. Citing sources shows which ideas are yours and which are borrowed from others. Failing to cite sources is considered plagiarism, a form of cheating.

When citing sources, you must cite both direct quotes and ideas paraphrased from others. Even if you do not use the author's exact words, if you used an idea from someone else, it must be cited.

For example, suppose Jane Doe wrote, "Thirty percent of students do not properly cite information," in 2009. You would need to cite her both if you quoted her directly (Jane Doe said, "Thirty percent of students do not properly cite information") or if you summarized what she wrote (Nearly one-third of students do not use citations correctly).


Copyrights do not last forever. When copyrights expire, the works are considered part of the public domain. Right now, most works published prior to 1923 are in the public domain while more recent works are covered by copyright. Currently, copyright laws are in effect for 70 years after the death of the creator of the work. So, if an author died in 2080, her books would not enter the public domain until 2150.

You should still cite sources for items in the public domain even though the copyright has expired.