Happy #PublicDomainDay!
Every year new works go out of the copyright monopoly and gets available for the public to use, remix, share, and do whatever they want with!
What enters the public domain varies according to each countries length of copyright monopoly, but there's a lot of international rules for this.
In the US all of Doyles Sherlock Holmes stories, the movie Metropolis, the song Puttin' on the Ritz, and a ton more great stuff is now available to build on! https://web.law.duke.edu/cspd/publicdomainday/2023/