Fair use is a legal doctrine that promotes freedom of expression by permitting the unlicensed use of copyright-protected works in certain circumstances. Section 107 of the Copyright Act provides the statutory framework for determining whether something is a fair use and identifies certain types of uses—such as criticism, comment, news reporting, teaching, scholarship, and research—as examples of activities that may qualify as fair use. Section 107 calls for consideration of the following four factors in evaluating a question of fair use: Purpose and character of the use, including whether the use is of a commercial nature or is for nonprofit educational purposes, Nature of the copyrighted work, Amount and substantiality of the portion used in relation to the copyrighted work as a whole, Effect of the use upon the potential market for or value of the copyrighted work.