There are basically five major legal differences between a copyright and
a patent : subject matter protected, requirement for
protection, when protection begins, duration, and infringement. There's
also a sixth practical one: cost.
Subject matter: A copyright covers "works of authorship," which
essentially means literary, dramatic, and musical works, pictorial,
graphic, and sculptural works, audio-visual works, sound recordings,
pantomimes and choreography. A patent covers an invention, which
essentially means a new and non-obvious useful and functional feature of
a product or process.
Requirement for protection: In order for a work to be copyrighted, it
must be original and fixed in a tangible medium of expression; no
formalities are required (see section 2.3). In order for an invention to
be patented, it must be novel (i.e., new), non-obvious, and useful and a
patent must be issued by the United States Patent and Trademark Office.
Start of protection