The Fair Use Rule, a component of copyright law, allows individuals to use an author's work without their direct permission. This hinders the copyright owner's rights to a small degree, but doesn't lessen their protection under the law. Professors, authors, printers, photographers and publishers should understand what constitutes fair use, and what spells a copyright law violation. This list is not self-contained, as most writers, students or scholars use quotes or paraphrase ideas in other published works.

The primary factor in in determining fair use is whether copyrighted materials is copied verbatim or used to create a new work, often described as transformative. Transformative works use protected material to create a new angle or take on a topic. The more transformative, the better. Questions relating to copyright law and fair use can be redundant, but the misinterpretation of each could be serious. Quoting or paraphrasing without an author's written permission, regardless of the fair use rule, can lead to a lawsuit.

Most often, fair use violations occur when someone misuses an author's words for commercial gain. For example, let's say a printing business decides to produce a brochure about paper production and distribution. They prepare original copy for the paper production section, but paraphrase another printer's brochure for the distribution section. That's not fair use. In order for it to be fair use, a printer needs to either create entirely original content for the brochure, quote the referenced material or use the other printer's information to create a new angle on the topic distribution.

Using research information in a new work is an example of the Fair Use Rule. Often it is imperative for an author to quote a short section in a scientific work to illustrate an observation. In addition, quoting a work in a review, to illustrate a point or to provide comment, is fair use. Professors and teachers use the Fair Use Rule when photocopying text or excerpts for classroom assignments or readings. However, unless it's absolutely clear that fair use applies to a publication, you should check the owner's rights under copyright law and request written permission.