Copyright protection is required in the US Constitution (among other documents) to be for a limited time, so protection must expire.
The laws have changed many times over the past 200 years, so you would need to know when a particular work was published before you can figure out when its copyright would expire, and whether other factors are involved (type of work, nationality of author, copyright notice and renewal, etc).
You should also know that some works have no copyright at all and never did.
In most cases, for work published after 1923, copyright will expire at the end of the calendar year 70 years after the death of the original author.
In the United States, copyright protection lasts until 70 years after the author's death. Copyright protection for works by English pilot W.E. Johns is set to expire in 2038. But you don't have to worry about copyright, because:Quotations qualify as fair use under U.S. copyright law, which means that quoting a work is not copyright infringement.Citing a book for informational purposes does not require permission from the author. Only attribution, or crediting an author for the work, is necessary.
When a copyright expires, the work enters the public domain. In the public domain, the work is no longer protected by copyright law, and anyone is free to use, reproduce, or modify it without permission or payment.
copyright
Yes; because registration is not required, copyright protection is automatic.
Someone receives copyright protection for their work as soon as it is created and fixed in a tangible form, such as writing it down or recording it.
Both copyright law and grants of arms confer specific exclusive rights. These rights also can be passed to heirs, although copyright protection does expire.
Copyright protection is free and automatic, as soon as the work is fixed in a tangible medium.
To copyright quotes, you can include them in a larger work that you register for copyright protection. This will protect the quotes as part of the overall work. Additionally, you can also register individual quotes with the U.S. Copyright Office, but keep in mind that the quote must be original and meet the requirements for copyright protection.
Windows XP was published around October 25, 2001, and copyright protection lasts 95 years, so it will become public domain in the year 2096.
A work that is not subject to copyright protection would be in the public domain. Examples are works of the federal government (such as NASA imagery) or works for which protection has expired.
Copyright and patent protection is for a limited time, but trademarks can be protected for as long as they are in use.