This is how Google makes money

I know that the Google algorithms for placing simple text ads next to web page content has earned Messrs Brin and Page a gazillion point two dollars each. And a big part of the reason for their success seems to be the impentrability of their algorithm.
Take, for example, this page, a page from the The Emergency Email Network®,that shows the current weather forecast with links to information about severe weather and other things to worry about.

Why, after reading this forecast, I should then want to buy a Plumber's Pillow as a gift for our plumber? We like our plumber. He's a great guy and does great work and deserves gifts of all kinds. Google, somehow, thinks that I'll be thinking about that when I'm reading about storms coming.
Oh, and cosmetic dentistry, too.

Before & After Photos Marlborough MA, Cosmetic Dentistry