• It's supposed to balance the rights of creators and users. The U.S. Constitution granted Congress the right "to promote the Progress of Science and useful Arts, by securing for limited Times to Authors and Inventors the exclusive Right to their respective Writings and Discoveries." In other words, the founders wanted to encourage creativity by rewarding creators with an opportunity to protect and monetize their creations....for a specific period of time.  They also recognized that creators draw on a shared culture, so eventually all works become part of the public domain, which belongs to all of us.
• It's the law. Congress passed the most recent Copyright Act in 1976.  You can find the whole text in Title 17 of the US Code. The Act contains exceptions that allow you--especially educators and researchers--to use other people's copyrighted work in certain contexts.  It's important to ensure that any unauthorized borrowing of others' copyrighted works follows best practices and is defensible under U.S. copyright law.  If you are alleged to have infringed someone's copyrights then you may be able to assert a fair use right to void the infringement allegations. 
• It affects your daily life. Students and teachers, especially, must rely on other people's works in order to teach, complete projects, and do research.  Copyright and fair use impact you even when you don't think about it.

Copyright is part of intellectual property law.  It gives creators exclusive rights (for a limited time) to print, copy, publish, perform, film, or record original works that they have fixed in a tangible form.  Putting something in a tangible form might include publishing it on a blog or writing it in an email.  Copyright specifically protects literary, dramatic, musical, and artistic works, such as poetry, novels, movies, songs, computer software, and architecture. Copyright does not protect facts, ideas, systems, or methods of operation, although it may protect the way these things are expressed.

• If you are looking for materials you can freely re-use and copy, check out the Free-to-Use Resources section for information about finding images, books, articles, and more that are either in the public domain or are specifically licensed to permit re-use.
• If you want to re-use someone else's work, you may be able to do this without seeking permission after conducting a fair use analysis. 
• If you're a teacher there are specific exceptions to copyright that you can learn about under the Copyright in the Classroom tab. 
• If you're a creator and want to learn more about using other people's work in your publications, and how to protect your own rights, check out the Author & Creator Rights section.
• If you need to use another's work but don't think it would qualify as fair use, see Getting Permission.