Reputation is a concept that we use in many aspects of our social life and as part of our decision making process. We use reputation in our interaction with people or companies we do not know and we use it when we buy merchandize or reserve a room in a hotel. However, reputation plays also an important role in the internet society and enables us to establish trust which is essential for interaction in the virtual world. Reputation has several important aspects such as Aggregation, Identity and Transitivity which make it applicable in completely different domains. In this presentation we show the use of these aspects in several different domains and demonstrate it with our own previous and current research on reputation.A good name is more desirable than great riches; to be esteemed is better than silver or gold.Proverbs 22:1