Q. What is Copyright?
Copyright is a form of protection provided to "original works of authorship" such as musical, literary, artistic, or dramatic works. These can be published or unpublished, but they must have a tangible form. You can't copyright an idea.
If you wish to use a copyrighted work, you need permission from the copyright owner who may also require some type of reimbursement for use of that work. The length of copyright protection currently lasts the life of the author +70 years or 95-120 years for an organization. The exact details of copyright are dictated in Title 17, U.S. Code.