What's the purpose of modern day communications...?

Recently , while surfing the internet and glancing thru my updated profile on FaceBook , I came across that some of my schoolmates from secondary school as well as some of my personal friends , decided to keep their personal information to the minimum . Or should I just plainly put it as barring the connected friends from viewing his or her profile . If this is the case , then why in the first place add that individual as a contact friend ? What is the purpose of FaceBook ( FB ) then ? While some individuals prefer to keep their personal information and biodata profile confidential , then there are some other individuals who enjoys broadcasting to the whole world about what is happening in their life and to some , keeping us updated every hour of the day about what is happening to them ( do these people have a life besides FB ???!!! ). Of course you can use other communication networks like Twitter and Diggs for those hourly updates but FB ? We tend to misinterpret the tools of modern communications these days. We have even failed to keep our personal life and living personal anymore . It seems that we want the whole world to know what is happening to us . How sad that confidentiality has no longer has it's meaning in today's world. Our privacy for living has been invaded by modern modes and means of communication. So - have you ever thought twice or thrice before sharing your personal life and information on the internet ?