How did the Internet start?

Mention the history of the Internet to a group of people, and chances are someone will make a snarky comment about Al Gore claiming to have invented it. Gore actually said that he "took the initiative in creating the Internet" [source: CNN]. He promoted the Internet's development both as a senator and as vice president of the United States. So how did the Internet really get started? Believe it or not, it all began with a satellite.
It was 1957 when the then Soviet Union launched Sputnik, the first man-made satellite. Americans were shocked by the news. The Cold War was at its peak, and the United States and the Soviet Union considered each other enemies. If the Soviet Union could launch a satellite into space, it was possible it could launch a missile at North America.