Are we safe on the Internet?

When a malicious person or person (s) got into my mail and solicited 1200 pounds from my contacts, I sent a warning message to all my friends telling them about the ‘hacker’. But Peter a good friend of mine corrected me saying that is a ‘cracker’ and not a ‘hacker’. Anyway I got to understand the two words just the way am learning how to keep my email more secure.
Just recently an organisation I was doing some work for got the whole website cracked into and erased or something like that. What I know is when we tried to log on there was nothing except empty pages.
Through my status updates on Skype and Facebook, a friend notified me that it is the age of hackers and crackers.
But just how secure can we be on the internet. A lot of my friends from around the world wrote or called to find out where exactly I am. That means most of the people I know are Smart in today’s speak. I have been doing some research on the internet to find out how we can increase our internet security. I got 99 tips that I think can be helpful to everyone. If you have more tips on how we can increase our security on the internet, please share with us.