Copyright law in the United States covers "original works of authorship that are fixed in a tangible medium of expression". This includes books and articles published in the United States after 1925, unpublished manuscripts, photographs, video and audio recordings, and other similar materials. Copyright law, however, does not protect general ideas or concepts, spoken lectures (that are not recorded), or elements of design (such as ways of laying out a website). Be aware that these may, however, be protected by other laws such as patent or trademark. For an overview of Copyright Law in the United States, go to http://guides.library.upenn.edu/copyright for more information and resources.