The Internet can be defined as a network of computers networks (indeed a network of networks rather than a network of single computers), distributed on all the globe, that rely on a set of communication protocols collectively known as TCP/IP, that allows communication, exchange, storage of information for it’s connected users. Figure 1-1 illustrates the worldwide distribution of the Internet network and the fact that several, often redundant communication paths are available (symbolized by the colored lines in the figure) to connect two nodes of the network.
Redundancy is a basic feature of the Internet. Back in 1960, the networks that then evolved into the Internet as we are currently familiar with, were commissioned by the Government of United States in order “to build robust, fault-tolerant, and distributed computer networks” (source:wikipedia). The reason for redundancy is that should a node of the network, or a communication route (a wire of some kind) stop working or go down for any reason, the network as a whole will remain up and running. This of course has implications in case of war, or catastrophic natural events.
To get more information on the history and other aspects of the Internet, please visit the Internet page on wikipedia.
You can continue reading about how data is transmitted on the Internet