public domain

public domain
—n
1.	(US) lands owned by a state or by the federal government
2.	the status of a published work or invention upon which the copyright or patent has expired or which has not been patented or subject to copyright. It may thus be freely used by the public
3.	in the public domain able to be discussed and examined freely by the general public

public domain definition

(PD) The total absence of copyright protection. If something is "in the public domain" then anyone can copy it or use it in any way they wish. The author has none of the exclusive rights which apply to a copyright work.
The phrase "public domain" is often used incorrectly to refer to freeware or shareware (software which is copyrighted but is distributed without (advance) payment). Public domain means no copyright -- no exclusive rights. In fact the phrase "public domain" has no legal status at all in the UK.
See also archive site, careware, charityware, copyleft, crippleware, guiltware, postcardware and -ware. Compare payware.