Once upon a time, a computer user named Yen wanted to know where his computer data lived, so he could control what happens. This page and others try to answer his questions about the spatial location of data. We also consider what the data looks like and how it is organized, since this affects Yen's freedom. These pages are not very technical in nature. Yen and other readers need only basic familiarity with computer usage to understand.
Yen uses software to write text documents and send email, and surfs the web with a browser.
Yen saves most of his documents on a hard disk, in files within his computer's operating system. Yen often browses the files in his computer to find things he saved earlier. Most things were once on Yen's hard disk. But now Yen uses the web, and he realizes some content lives someplace else. This is most of what Yen needs to know to understand these pages.