The Motion Picture Association of America has anti-piracy sniffing dogs.

Sam buys a new band's CD but decides he doesn't like the singer, so he resells the CD on eBay. That's legal.

The sole purpose of copyright is to make authors money and protect them from getting their works stolen.

Amy tells Daniel about her summer vacation, and he says he'd love to see her pictures. Amy uses a peer-to-peer (P2P) file-sharing program to upload the photographs she took at camp so he can download them. That's copyright infringement.

Amy tells Daniel that the files are available. Daniel uses the same peer-to-peer file-sharing program to download Amy's camp pictures. That's copyright infringement.

Jason copies the entire last chapter from the final Harry Potter book to his commercial blog without any additional commentary. Since he only used part of the work, Jason would be protected by fair use.

Kathy downloaded a few photos of local organic farms from Flickr.com's Creative Commons (CC) pool. She follows the rules of the photographer's specific CC license and uses them in her digital video about sustainable agriculture. That's OK.

Dwight finds a peer-to-peer (P2P) network that offers free music downloads. He owns all but one of his favorite band's CDs, and he finds that particular CD on the network. He's too cheap to buy it, so he downloads the songs. He's not committing copyright infringement.

Paula read an interesting article about the making of the film Titanic and wants to use a short quote in her cinema review paper for journalism class. That's copyright infringement.

The Public Domain is a polar research station in Antarctica.

Adam recorded a video for his YouTube channel about the upcoming Senate elections and includes an official photo taken by a government employee and four bills authored by the incumbent that Adam found on the Senate's website. That's copyright infringement.

Justin downloaded the black-and-white horror classic Night of the Living Dead from the Internet Archive and decided to mix an audio sample from the film into one of his original songs. That's copyright infringement.

Since Richard forgot to register his screenplay before he sent it out to agents for review, he's no longer eligible to copyright it.