Final answer:
A creative work or invention that cannot be owned is said to be in the public domain, allowing free use and distribution by anyone.
Step-by-step explanation:
When a creative work or invention cannot be owned it is said to be in the public domain. This means that anyone can use, reproduce, and distribute the work without permission and without paying copyright royalties. Works enter the public domain under various circumstances, such as when copyright expires or when the creators forego their copyright and place their work in the public domain intentionally. For example, a work might enter the public domain because the copyright term has ended, which is often the author's life plus a certain number of years, varying by country. Many classic literary works, art pieces, and inventions have moved into the public domain, allowing for free and legal distribution and modification by the public.