 The standard of "supersed[ing] the use of the original work" would be widely cited as a standard for the degree to which a work was transformative when fair use had become more clearly fixed as a legal principle.In the Copyright Act of 1976, Congress defined fair use explicitly for the first time, giving as one factor "the purpose and character of the use, including whether such use is of a commercial nature or is for nonprofit educational purposes".This factor was later determined to hinge in substantial part on transformation.