How Is Copyright Different From Plagiarism?

Copyright concerns properly credited sources. Even if the sources are credited, excessive use of the original source may be copyright infringement. Plagiarism on the contrary, is an act of using the ideas and/or words of the source without giving it its due credit. Even if the ideas of the source are modified by paraphrasing or summarizing, its termed as plagiarism. Plagiarism is considered to be dishonest and unethical. Where copyright is concerned with the original idea of the source, plagiarism abuses the words and ideas of the source. Without originality, ideas and words can't be copyrighted. Except for specific statutes applied to results of scientific research carried out for the government, plagiarism doesn't appear in federal statutes. On the other hand copyright is addressed in both case law as well as federal statutes.