The legal ownership of a "work," which can be written text, program source code, images, sculpture, music, audio, video, pantomime, choreographic expression and architecture.
Before January 1, 1978, a work had to be published to be copyrighted. After that date, any work expressed in paper or electronic form is automatically copyrighted for the life of the author plus 70 years. Registration with the Copyright Office is not required, although it is beneficial if there are disputes later on. In the U.S., a copyright symbol is not mandatory, but recommended.
For works by an anonymous author or an author who uses a fictitious name (pseudonymous) as well as works "made for hire," such as a publication written by an employee of a company, the copyright lasts 120 years from date of creation or 95 years from date of publication, whichever is shorter. See
plagiarism,
fair use doctrine,
Creative Commons,
copyleft,
trademarks,
DRM and
image protection.
Copyrights Are Losing Their Value
In today's AI world, copyrights are ignored by many of the large tech companies. They gobble up everything written, photographed and filmed to use as training material for their AI models. Their claim is that they only "read" the content; however, that very same content is turned around to deliver results for users which causes the company's market value to increase. See
copyright infringement.