The original backbone of the Internet is based on an old military network called ARPANET which was built by ARPA in the late 1960's.ARPANET was built so information could withstand a nuclear war.The idea was not to have a single point of failure.This means if part of the ARPANET was blown up in a nuclear war,the rest of it will still work! What made ARPANET so successful was it's packet-switching technology, invented by lawrence Roberts.The idea is that "packets" of information have a "from" address and a "to" address.How they get from point "a" to point "b" depends on what roads are open them.Packet switching is a very elegant thing.Without it,the Internet would simply not work.