Information travels in packets from one computer to another. Sometimes pieces of information are too big to be sent in one packet, so the device quickly breaks it down into lots of smaller packets and sends it. The packets may take different routes and arrive at different times, but they are reassembled at the destination. Routers move information smoothly from one device to another, however there are lots of different routes packets can take, so if one router is broken or one route is congested, the packets simply travel along a different path. When they arrive at their destination, the TCP (Transmission Control Protocol) checks whether all packets have arrived. If they haven't, they will be resent. This plus the Fault Tolerant system is what makes delivering information via the internet so reliable.
