A transaction is a change of state, an information-transfer transaction is a transaction in which one of the following changes occurs: content, ownership, location, format, etc. An information-transfer transaction usually consists of three consecutive phases called the , the information transfer phase, and the . Examples of these consecutive phases are the copying and transporting of information. Once a transaction occurs there are also costs to consider, which are associated with that certain transaction. When it comes to the transfer of information some transaction costs include time and means (money).