What is in the "Public Domain?
As you might expect, it's somewhat complicated.
In most of the world, it's pretty straightforward - things enter the public domain (PD) a certain number of years after the death of the author. In most countries that number is 70 years, in a few (eg Australia) it's 50. That means that, for example, all works of authors who died prior to 1937 (as I write this is 2007) are currently PD in Europe; prior to 1957 in Australia, and that advances, year by year, as you would expect it to (eg next year it'll be 1938/1958).
In the US, the rules are rather more complicated, largely due to the political lobbying done by companies like Disney who are desperate that M. Mouse and co should NEVER enter the public domain.
Basically, in the US:
- Anything published prior to 1923 is PD.
- Anything published between 1923 and 1963, with a copyright notice, for which copyright was NOT specifically renewed, is PD.
- Unpublished works: Author's death + 70 years.
- Pretty much everything else: publication date + 95 years (and this date keeps getting extended as the "danger" approaches of anything new entering PD)
The net result of this is that some stuff is in the PD in the US, but not elsewhere (early works of authors who had LONG lives - eg Agatha Christie), and a LOT of stuff is PD outside the US but not in the US (works of authors published after 1923 who died before 1937/1957).
As the years go by, the balance is shifting - what is PD in the US is a static set of works, whereas elsewhere new material is entering the PD every year.
That, at least, is the basics!