Most of the time, Flash cookies contain extremely basic info -- like an ID number that tells a website you've been there before, or your preferred volume settings for a video. Sometimes they can store a lot more, like cached media or information that can be used to track you as you go from site to site across the InterWebs.
And that's where Malley's suit comes in. He's accusing these sites of illegally storing information without informing consumers they were doing so.
What's wrong with tracking people across the Web? Nothing -- if you ask advertisers.
The advertisers say that they a) collect this data anonymously and b) can use it to deliver more targeted (and thus more "interesting") ads. If you're shopping for a car on, say, Edmunds.com, and you visit another site that uses the same ad network, it can show you ads for cars there, too, even if the site has nothing to do with automobiles, because it knows where you've been and what you've done. Ad companies can also attach other values to your cookie -- like, you're interested in sports, or you buy a lot of flowers, or you really like watching videos of cats singing opera.
Of course, to many people, the idea of anything following you across the Web, even anonymously, is just creepy.
Imagine a tiny man in a trenchcoat and a porkpie hat following you as you spend a busy day -- going to the bank, getting a haircut, wandering through the mall, stopping by your local for a cold one, and so on. The little man doesn't say a word, but every time you reach someplace new he takes out a stubby little pencil and jots down the address in his notebook.
Of course, he doesn't know your name, so everything's OK, right? Later you get coupons for haircuts and beer in the mail.
You can control Flash cookies, kinda/sorta. Adobe provides a Web page that uses a Flash plug-in (naturally) where you can turn these cookies on or off, control how much storage they use, and delete specific cookies. Good luck figuring out how to use it.
Just what we needed: Another Internet privacy threat to worry about. I guess this must be the year for them.
Do you worry about Flash cookies? What privacy threats really bother you? Post your hopes and fears below or email me: email@example.com.
This article, "Attack of the Flash cookie zombies," was originally published at InfoWorld.com. Follow the crazy twists and turns of the tech industry with Robert X. Cringeley's Notes from the Field blog, and subscribe to Cringely's Notes from the Underground newsletter.