If you wanted to erase your digital footprint, could you do it? Probably not, concludes a report earlier this month in the San Francisco Chronicle.

Your digital footprint is all the information that exists about you in computers all over the world, linked together by the ‘Net. The information is collected anytime you do anything on the Web — use your credit card, e-mail on Google, search for a book, or register for a free e-newsletter on cheap air fares.

Some information you know is being collected, because you give it — such as personal information to set up an online account. Other information gets collected through “cookies,” electronic “spies” that send reports of what you’re doing online.

And of course there are the myriad public records about us that data companies have collected and put on the Web. The companies make a hefty profit selling the information.

To counter all this data collection, new companies that promise to erase data about you have sprung up. There’s ReputationDefender, for example. But even it doesn’t promise it can wipe your digital slate clean.

U.S. law doesn’t give citizens the right to have invasive or personally identifiable information deleted. By contrast, European countries do.

One way to drop out of digital sight may be to let your online information grow old. That makes it less accessible since older information is placed lower in search results.

Another way — change your name and move to a new address.

But generally, the picture painted in the Chronicle article is that digital anonymity is an oxymoron.