What is Public Domain Day?
Copyright protection is only temporarily. Works created in The Netherlands are commonly free of copyrights on January 1, 70 years after the original author died. That is why the first day of the year also is referred to as Public Domain Day, a day to celebrate that new works have become available in the public domain.
The work of these people can be reused. For example, they are used on Wikipedia, remixed to new works and can be used for new publications.