this is the internet

By way of a conversation I was just having with someone, I realized how easy it is to find out all about a person. It's a simple step-wise deduction process by which you can get that person's complete personal details.

I also realized how scary it is for an average user to find out that the complete stranger you just met on the Internet knows so much about you.

Some years ago, you'd need to hire a detective to do this sort of stuff. But in this age of information technology, all you need is some logical deduction skills, and an Internet connection.

Let me give you a very very basic example of this. When you sign up for email, you enter a desired username, along with lots of private, priviledged information like date of birth, address, etc. So when the username is taken, the email provider conveniently suggests alternatives like username_74 or username_Delhi. A crime in the name of usability, in my view. The user quickly chooses one of these IDs without much thought, but from now on, every person that he writes to knows that Mr. User is 29 years old, or he is from Delhi.