Copyright does not last forever; when copyright expires, the work is considered to be "Public Domain". Material that is in the public domain does not require copyright permission as long as it is properly cited. The general rule of thumb for public domain in Canada is 50 years after the death of the author, but there are exceptions to this.
After copyright expires, and a work becomes part of the “public domain”, it can be freely copied, distributed, adapted and performed without having to request permission from the author or having to pay any royalties.
The public domain should not be confused with works that are publicly available. Many publicly available works are protected by copyright.
