The terms piracy and theft are often associated with copyright infringement. The original meaning of piracy is "robbery or illegal violence at sea", but the term has been in use for centuries as a synonym for acts of copyright infringement. Theft, meanwhile, emphasizes the potential commercial harm of infringement to copyright holders. However, copyright is a type of intellectual property, an area of law distinct from that which covers robbery or theft, offenses related only to tangible property. Not all copyright infringement results in commercial loss, and the U.S. Supreme Court ruled in 1985 that infringement does not easily equate with theft.
What kind of property is copyright used for? (If the question is unanswerable, say "unanswerable")
intellectual property