Centralized is simple, a single entity has final say on all rules within the system, they can enforce the rules, change them, and ignore them to the degree they see fit. Websites would generally fall into the centralized category. Distributed means multiple entities by some sort of process have come to have final say on the rules of the system, the control and relationships between these entities may change over time but ultimately this collaboration is the one in control. An example of a dis...