"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." U.S. Const., art. I, § 8, cl. 8.
With some exceptions, copyright protection applies to "original works of authorship fixed in any tangible medium of expression" (17 U.S. Code §102a). Note the words "original" and "fixed" - it needs to be both things. For example, if you have an original idea for a poem but have not expressed it in a tangible medium, that poem is not protected by copyright.
Section 106 of the 1976 Copyright Act gives the owner of the copyright the exclusive right to do and authorize others to
This list is from Copyright Basics (2012) available at https://www.copyright.gov/circs/circ01.pdf
This list is from the Claremont Colleges Library's copyright guide under "Copyright Resources: What is Covered by Copyright." http://libguides.libraries.claremont.edu/copyright-resources/copyrightprotection