Works in the public domain are all works that are not covered by copyright. These works belongs to the public and there are no restrictions on their use. It most often applies to works on which copyright has expired. In Canada, the term of copyright is, in most instances, for the life of the creator plus 50 years (ending on January 1 of the year following the 50-year period). After that, works enter the public domain.
Copyright law is national. Works may be in the public domain in Canada, but not in other countries. In the late 1990s, the term of copyright coverage in the US and most of Europe was revised to life of the author plus 70 years. If a work is copied or used in Canada, the 50-year rule applies. Keep this in mind when using US and European sources that claim ownership over works that are free to use in Canada. If a work is to be used outside of Canada, the laws of the location it will be used apply.
Original editorial, annotative or translation work added to a public domain work may have its own copyright and could affect your ability to use it without permission.
The law regarding the jurisdiction over websites whose content may be accessed in multiple countries is not settled. This means that you should exercise caution in posting public domain works to publicly accessible websites when they can be accessed in countries where the works have not yet entered the public domain.
Authors may waive all or part of their copyrights. When an author has waived all rights, the work is in the public domain. When part rights have been waived (such as with a Creative Commons licence) the work may be used within the terms of the licence without having to seek permission.
The Canadian Public Domain Flowchart provides a guide to help determine if a work is in the public domain in Canada.
There are exceptions to the "life plus 50" rule for works by joint authors or unknown authors, unexploited works/posthumous works, government/Crown works, photographs, cinematographic works such as films and videos, sound recordings, performer's performances and communication signals.
Sometimes a copyrighted work has a "blanket permission" statement that allows the free use of the work without the need to get permission. Look inside a book or on the home page of a website for a section called Copyright, Permissions, Terms and Conditions, Legal Notices, About Us, etc. to see if such a statement exists.
To find a work in the public domain or a work that can be used without paying royalties, search the Internet by the type of work you are interested in (for example, search for "public domain films"). Also, check the terms under which web content can be used by looking on a website's home page under Copyright, Permissions, Terms and Conditions, Legal Notices, About Us, etc. for restrictions before copying, modifying, adapting, distributing or using content.
Parts of this section were adapted from the University of Manitoba copyright website under a Creative Commons licence.