Is there really such a thing as a free lunch? Nothing is ever free, and that applies doubly so for the internet. That “free” service you are using is actually costing you far more than you might think. Always remember that when something appears to be free, that you or somebody else is paying somehow.
How many times have you surfed to a new site, only to be asked for your name, birthday and gender? Did you enter the information that was requested? Use cause if you value your privacy.