A distributed network is a computer network that has no one central repository of information or control, but is comprised of an interconnected web of host computers, each of which can be accessed from virtually any point on the network.
The Internet is a distributed network. An Internet user can obtain information from a host computer in another state or another country just as easily as obtaining information from across the street, and there is no hierarchy through which the information must flow or be monitored. Instead, routers throughout the network regulate the flow of data at each connection point.
By contrast, in a centralized network, all users connect to single location. The distributed nature of the Internet gives it robust survivability characteristics, because there is no one point of failure for the network, but it makes measurement and governance difficult.