Cookies, Cache, and Other Security Options

Cookies are something like Web page preference files. Certain Web sites—particularly commercial ones like Amazon.com—deposit them on your hard drive like little bookmarks, so they'll remember you the next time you visit. Ever notice how Amazon.com greets you "Welcome, Chris" (or whatever your name is)? It's reading its own cookie, left behind on your hard drive (or in this case, on your iPhone).

Most cookies are perfectly innocuous—and, in fact, are extremely helpful, because they help Web sites remember your tastes. Cookies also spare you the effort of having to type in your name, address, and so on, every time you visit these Web sites.

But fear is widespread, and the media fans the flames with tales of sinister cookies that track your movement on the Web. If you're worried about invasions of privacy, Safari is ready to protect you.

To check all this out, from the Home screen, tap Settings→Safari. The options here are like a paranoia gauge. If you click Never, you create an acrylic shield around your iPhone. No cookies can come in, and no cookie information can go out. You'll probably find the Web a very inconvenient place; you'll have to re-enter your information upon every visit, and some Web sites may not work properly at all. The Always option means, "oh, what the heck—just gimme all of them."

A good compromise is From Visited, which accepts cookies from sites you want to visit, but blocks cookies deposited on your hard drive by sites ...

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