Let's start at the beginning, with a definition of public domain.

What we’re talking about here is a particular definition of public domain, having to do with the copyright status of creative works. (This tutorial isn’t about the land owned by the US government, which is also referred to public domain.)

Many people think the definition of public domain is “freely available.” They believe that creative works (including articles, images, videos, music, software) available on the Internet are fair game because they’re in the public domain. The fact is, they’re wrong. Even though something is freely available and easy to copy, that doesn’t mean it’s in the public domain.

Put simply, the public domain consists of works that aren’t protected by copyright or by other legal means. You are free to use public domain works however you wish, without seeking permission, because ...

their copyrights have expired; or
the copyright owner didn’t follow certain required formalities (so they didn’t get a valid copyright); or
the works weren’t eligible for copyright in the first place; or
their creators dedicated them to the public domain.

That’s the definition of public domain we’ll be dealing with here. Okay, now that we can define public domain, are you ...

Ready for some detective work?

Since there’s no directory or list of public domain works that you can consult ... you must gather some facts about a work before you can figure out if it’s in the public domain. But you can figure it out.

What facts do you need?

You need to know whether:

the work is eligible for copyright protection in the first place
the work is published (and, if so, when and where)
the work was published with a valid copyright notice
the work’s copyright has expired
the copyright owner had to renew the copyright, and if so, whether renewal took place (this will depend on the year the work was first published)
the work is a derivative work
the work is a compilation
any other laws protect the work
the work’s copyright has been restored

Sound like a lot? It’s not so bad, actually.

Alrighty then ...

Since our definition of public domain means lack of copyright protection, we’d better get clear about what copyright is. Looks like it’s time for a quick definition of copyright ...

Let's start at the beginning, with a definition of public domain.

Ready for some detective work?

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