Introduction

Abstract

Although the saying above is an old one, it is surprisingly applicable to the Information Age we are living in now. We are flooded with social networking sites on which we can manage our friends, relatives, or business relations. Some of them are merely used to keep track of our acquaintances, but others can be quite convenient for other purposes too, think e.g. of the business oriented social networking tool LinkedIn or the image hosting website and online community Flickr. Many other useful applications will follow in the next sections.

It’s not what you know but who you know that makes the difference. Anonymous