Wikipedia aims to distribute free content worldwide in any and all media—including the images used in its articles, and even images uploaded to its repository for potential use in articles. What does that mean to you? It means you can download almost all of these images to your computer, free of charge.
If you see an image in a Wikipedia article that you'd like to have, just click it. You'll see a new page showing a larger image, as shown in Figure B-17.
Figure B-17. The file Image:Fujisan from Motohakone.jpg is used in the article Tokyo. Clicking the thumbnail image in the article shows you this larger image, though not necessarily a full-sized image. Click "full resolution" to see the full-sized version. Right-click the full-sized image to save it to your computer. You can also save the image as your new desktop background image.
The vast majority of images on Wikipedia are free content—they're in the public domain or have Creative Commons licenses, for example. But if you come across an image labeled as a "fair use" image (a screenshot of a commercial software program, for example), don't treat it as free content. Don't download it unless you're sure you're not infringing a copyright by doing so.
Several years ago, the Wikimedia Foundation realized that it didn't make sense to have images stored on language-specific Wikipedias, so it created the Commons (http://commons.wikimedia.org) as a central storage area available to all language Wikipedias. Think of it as a stock media site for Wikipedia and other Wikimedia Foundation projects (it has sounds and other media files as well as images). In fact, the image in Figure B-17 is actually in the Commons, not the English Wikipedia.
Because the Commons is a media storage site, you'll find a table of contents right on its Main Page (Figure B-18). With more than 3 million images and other media files, you may find something you really like—and it's all free content.
Figure B-18. The Commons' Main Page offers a number of ways to view its content—by starting with featured pictures, by drilling down through categories, or by choosing a topic area. If you choose a topic, you'll arrive at a category page similar to Figure B-5 with one interesting difference—the page has a tab labeled CatScan. Yep—that's the category intersection tool mentioned on Articles in two different categories, and it works for the Commons as well as Wikipedia.
If you'd like a free, high-quality picture emailed to you each day (or, to be technical, a link to such a picture), you can subscribe to the Commons' Picture of the Day mailing list. Sign up at http://lists.wikimedia.org/mailman/listinfo/daily-image.