The idea is you register for a website, service, or app with an email mask, which then forwards on the email to your actual account. I was in a hurry the day I booked this hotel, and so I skipped using an email mask. 2) A virtual phone number would have helped, tooYou can hide your phone number just like you can an email address—phone masks exist too. The benefit is twofold: Hackers and data brokers alike can’t build a detailed profile on you with that info, when it’s inevitably lost or sold. 3) A virtual credit card numberThe email about the data breach was quick to assure that no credit card data had been stolen, but I still kicked myself anyway for using the same card I’d brought with me on vacation.