[qwertox]

Super interesting article.

> but those files are internal categories Google uses to classify user data.

I really want to know what kind of classification this is. Could you at least give one example? Like "Has autism" or more like "Is user's phone number"?

[StephenAmar]

The latter. Like is it a public ID, an IP, user input, ssn, phone number, lat/long…

Very useful for any scenario where you output the proto, like logs, etc…