Do you have a internet friend?

A couple of years ago, cyworld was boomed very much. Everybody has their own blog and visited their friend's blogs. I was one of them who found it interesting. what do you think it makes people crazy about it? I think it was so fun for them to make relatives in the web. Also without spending lots of time, they could see their friends in the web. Cyworld ,New media technology, reinforced existing social networks, but also worked to isolate people. You may know what i mean.
Here, when you do cyworld, you probably visited your friend's friend's blog, forthemore friend's friend's friend's blog as well. There was a funny experiment by Stanley Milgram in 1967 “The Small World Problem”. the thing is that he sent 60 letters to his friends in some area and asked to forward the letter to the wife of someone living at a specified location where is far from his friend's ,who was asked, area. His friends was also asked only pass the letters by hand. The funny thing is that most time, the letter was delivered in six steps. It is called “six-degrees of separation”. Is that funny?

Okay, Let's talk about Amazon, onlive shopping website. My professor Yoon bought several books there. i think those was related to his studying - I mean some specific field. After that Amazon recommanded he buy some books which is relatived in that field, too. That was amazing How amazon knows Dr.Yoon's interesting and could recommand some books.
Amazon gathered his information like his intersing and what he has bought. They used recommender systems; amazon.com’s feature: “People who bought this book also bought the others".
Another example of gathering information is a Google search engine. when you type out Bush to search some information about it, Google search engine just do not show us some websites hyperlinked to Bush. it connect us to webpages considered popular. What makes it possible is Google’s Page Rank algorithm gives more weight to popular webpages. Very smart.
Think about that if you are a manager of some company, you would want to know whole system of the company, not detail part of it. In the same way, there is a cybergeography like a map visualizing networks. It could be helpful for them who are interested in knowing whole pattern in networks. Thank you for the lecture. ^^