The Deep Web is that part of the Internet that is hidden from search engines such as Google and Yahoo! It’s the part of the web you can’t find unless you know about it. Researchers say that the Web we use on a daily basis is actually just the tip of a huge underground mountain, and that the Web we know is probably only about 1% of the Internet.
So, what else is out there? Included in the Deep Web are databases both public and private. Examples of public databases include the U.S. National Oceanic and Atmospheric Administration, NASA, the US Patent and Trademark Office, and the Securities and Exchange Commission’s EDGAR search system. Private databases require membership to access, and include the academic database Elsevier, and the law database LexisNexis. These databases make up approximately 54% of the Web.
Another 13% of the Web consists of private intranets run such as those run by companies and organizations.
The rest of the Web is the dark part of the Web known as Tor. Tor (short for The Onion Router) was originally designed by the U.S. Navy as a way to secure online communications. It is now a non-profit. Unfortunately not all Tor users are good guys, and Tor has become a hotbed of illegal activity that includes the selling of drugs and private, illegal information, such as Social Security numbers and stolen credit card numbers.