We collect and analyze aggregated data about your behavior on our website, such as which pages are most popular, where visitors come from and so on. Individual "footprints" though the site are available to us if we really dig into the raw logs, but we're not interested in that, have never looked at them, and can't think why we ever would.
We began using Google's Display Advertising service in January 2014. We use the Demographics and Interest Reporting features to understand which types of people are most engaged by different parts of our site. Google tells us the age ranges and topical interests of visitors, again in the aggregate. Not at the individual level.
You can see what Google knows about you here, and make adjustments too. Given current concerns about online privacy, we think it's a good idea that Google asks us to make our privacy policies clear to visitors before they provide us with these services.
We will not share your email address with anyone, ever.