Radon is a dangerous gas. It is colorless and odorless and is always being emitted from our planet-don't worry, it's not enough to harm you.
Copyright for published works in the USA has been according to a federal copyright statute, since the first U.S. copyright statute in the year 1790. Before the Copyright Act of 1976 became effective on 1 Jan 1978, unpublished works were. protected by state law, known as common-law copyright.
These written works represent an expenditure of time, money or both. Copyright law is the legal recognition of the intellectual property rights of an author to a written work. Understanding how and when copyright law applies to a document is vital to protecting your investment in it.