Copyright is a form of intellectual property protection that gives the creator of an original work the exclusive right to use and be credited for it. Generally, you do not have the right to use someone else's copyrighted work without permission or a fair use defense. However, there are a few scenarios in which you may be able to use previously copyrighted work even without a fair use excuse.
Section 106 of the current U.S. Copyright Act (U.S. Copyright Act, 17 U.S.C. §106) grants six exclusive rights to copyright holders. These rights are:
1. To make copies or recordings
2. To create derivative works
3. To distribute copies
4. To perform a work publicly
5. To display a work publicly
6. To perform sound recordings by digital transmission. 
These six exclusive rights represent the entirety of the rights of copyright owners and exist only for a limited time. During the time that a work is under copyright, nobody except the copyright owner has the right to do any of the things stated in Section 106 without the permission of the copyright owner (unless the use is considered “fair use").
Copyright Law and Policies
Licensing and Using Copyrighted Materials
What can be copyrighted?
According to Section 102 of the Copyright Act, in order for a work to be eligible to be protected by copyright law in the U.S., it must be an original work of authorship “fixed to a tangible medium of expression.” This statement contains three distinct criteria:
1. It must be an “original” work of authorship, meaning that the author made some kind of substantial creative contribution
2. It must be “fixed,” that is made sufficiently permanent or stable
3. In “any tangible medium of expression,” which means it must reside somewhere that allows it “to be perceived, reproduced, or otherwise communicated for a period of more than transitory duration.” (17 U.S.C. §101)
Currently, for any work created in 1978 or after that date, copyright is assigned at the moment that a copyrightable work is fixed into a tangible medium. (17 U.S.C. §301) According to Section 106 of the Copyright Act, a work is copyrightable if it required some (even very small) degree of originality and is fixed in a tangible medium. (17 U.S.C. §102(a))
What can't be copyrighted?
Some categories of works fall outside of copyright protection. These works are in the public domain, meaning they are entirely freely available without copyright restrictions. Any work that fails to meet the criteria previously discussed (original works of authorship fixed in a tangible medium) falls into this category.
The following are categories of works that cannot be copyrighted:
 Kenneth D. Crews, Copyright Law for Librarians and Educators: Creative Strategies and Practical Solutions, 3rd ed (Chicago: American Library Association, 2012).
 Ibid., 15-19.
Works created and published before 1928 are in the public domain and may be used freely, and works published between 1928 and 1978 may or may not be under copyright, depending on the observance of copyright registration formalities (17 U.S.C. §304).
The duration of copyright for any works created during or after 1978, or created but unpublished by 1978 (U.S.C. §303), is generally the life of the author plus 70 years, or if a work of corporate authorship, 95 years from the date of publication or 120 years from the date of creation, whichever occurs sooner (17 U.S.C. §302). However, there may be exceptions depending on when the work was published and whether it includes a copyright notice. The links below are useful to determine the copyright status of a work based on the year of creation or publication, the presence of a copyright notice, and the status of the author.