Is there a difference between private and public?

It is a wild world when your private internet searches in the comfort of your own home are no long private. When the search engines you use save all of you past searches. Where do we draw the line between public and private?
It is legal for search engines to save your searches. For what reason we are not sure, but there is no current law stopping the archiving of individuals internet inquires. And it is very interesting that the major search engines are working to hype up there search speed to pull users away from going directly to the page they are seeking, almost making it mandatory to visit there site first. And let’s not forget that they are saving our search inquires. Could it be possible that some here has ulterior motives? I am not proposing anything I am just looking at this with a defensive attitude.