Relevant content in the unit: Unit 3.2, Acquiring Essential Knowledge, What types of content can be CC-licensed, suggested additional content (related to both paragraphs in current content).
While the primary purpose of this paper is about 3-D printing, this resource is a great overview of copyright law related to electronic files, whether they be photographs or the files for a 3-D printing project.
This is an especially good resource for those interested in specific examples of the delineation of the functional, non-copyrightable aspect of a work and the artistic expression, copyrightable aspects of a work.