Privacy?

I am curious about a good definition of Privacy.  I hear the term bandied about on almost every fear issue from healthcare to credit card fraud to back yard barbecues.  

As a member of the class of credit card users that have had to change numbers more than once, the word privacy isn't the first word that comes to mind; I think of nasty little boys turning to grown men prying their way into locked storage facilities to garner ways to get more free toys.  

On health care, malicious distribution of personal information that may affect my job, friends, or family.  Employment is had enough, without you name on a list of patients with Cancer, MS, or Aids.

A downwind neighbor with a video camera mounted on his roof, aimed at my back yard to monitor our use of our fire pit, and  barbecue is a severe invasion of privacy, though the police refused to act.

  

I look at Google's privacy policy, and the idea of them tracking my shopping habits, website viewing, et cetera - all done without my  "like your name, email address, telephone number or credit card" is simply data collection on a reasonable level, and not truly a privacy issue.  Obviously, I am struggling with where the line is, and so are many others.  

What the hell is privacy?  If I walk down the street and someone snaps a photo, have they invaded my privacy – well no, I’m in public, but if I am in my bedroom then yes, because I expect to have privacy.  But that can’t be the rule.  If I am on the internet, I am sure there are thousands of little grown boys trying to get their jollies off by intercepting some tidbit of my activity.  Do I expect privacy there?  I don’t know.  I hope so, for my credit card info.  I hope so if I am buying something sensitive – could be anything – lotion, lathe, or lettuce seeds.  I am not a very private person;  let my feelings, ideas, and preferences spill all over my family, friends and Facebook.

At dinner with our good friends and neighbors the other night, Mrs. S. stated that she was now having terrible issues with her computer banking.  She had deleted all her cookies as an attempt to maintain privacy, but now, she cannot contact her bank online, where she posts all her bills to be paid throughout the month.  "That's what I was told to do" as she shrugged, unable to produce a source.  I really don't know what to tell or do for her now.  What she had done was extreme, but consistent with the advice of many purported experts.  You know, all those columnists and bloggers that claim to know how to protect us.  

This entire subject is confusing to most people.  I would hope you could spread some light on this area We all understand that privacy is precious, but few can explain it beyond someone taking pictures of us in the bathroom  

Privacy seems to be much like pornography. A phrase was famously used by United States Supreme Court Justice Potter Stewart to describe his threshold test for pornography in Jacobellis v. Ohio (1964). I shall not today attempt further to define the kinds of material I understand to be embraced within that shorthand description ["hard-core pornography"]; and perhaps I could never succeed in intelligibly doing so. But I know it when I see it, and the motion picture involved in this case is not that