For most of its existence, Internet was used primarily by schools and government agencies as a way to share information. Then, several things happened in quite a short period of time, which all combined together and resulted in a dramatic change of the Internet structure; it became commercial. The emergence of HTTP and the web browser, breakthrough in bandwidth technology, increase of processing power and slashes in price, combined with the global position Microsoft achieved on the market with it's line of products, caused the Internet to probably be the next Babel tower. Before, Internet was a few thousand of Unix boxes, administered by computer professionals. Today, it have been invaded with millions of PC based machines running some flavor of Microsoft Windows, and anybody can have access to one. These machines come mainly from companies, where employees have Internet access, or from cable and DSL ISP customers (I omitted dial-up because of negligible bandwidth, but they are part of the problem also). These employees and customers, in the most part, barely knows enough to power their computer up and send e-mail, yet they have machines that are far more powerful in their hands. This is Achilles' heel of Internet.
2. Some quick talk about viruses
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