The Deep Web or the invisible web are parts of the world wide web that are not indexed by search engines. What we refer to as the internet is actually the surface web -- websites that have been indexed by search engines. There are millions upon millions of indexed web pages, but the deep web is, experts claim, up to 500 times larger than the surface web. Like data engineer, Denis Shestakov wrote in his paper, titled "Sampling the National Deep Web": "it can be assumed that the deep web is growing exponentially at a rate that cannot be quantified."

The good, the bad, and the dark

The deep web is commonly accessed through a program called Tor.

Tor is a free software that enables anonymous internet access. Deep web users typically browse the hidden part of the internet using proxies (spoofing their IP addresses) for protection and anonymity.

A lot of webpages in the dark web contain illegal content (which is why some of them were de-indexed by search engines), but most of them are private websites users can access only if they know their IP address. There are quite a lot of specialized forums and similar websites, but the most interesting thing about the invisible web is the illegal markets where drugs, counterfeit credit cards, weapons, and other illegal goods and services are sold.

The Silk Road saga

The best known darknet market was called the Silk Road.

Founded in 2011 by a young man named Ross William Ulbricht, the Silk Road quickly became the largest and most popular deep web marketplace. Illegal goods and services were regularly sold on the website and customers paid for them using an anonymous virtual currency -- bitcoin. This, in combination with proxy and Tor use, made these transactions virtually untraceable.

Things started going downhill for the Silk Road when Australian authorities intercepted drugs imported through the mail. Soon enough, the FBI caught up to the Silk Road and arrested Ross Ulbricht in October 2013 -- prior to his arrest, Mr. Ulbricht attempted to have six people killed. In fact, he wanted to hire contract killers that were offering their services on the marketplace that he had originally created.

Yes, even hitmen sold their services on the Silk Road.

The aftermath

The Silk Road, however, was not the only dark web marketplace. There are quite a few and some of them are still active. Websites like reddit have specialized communities in which vendors conducting business via these marketplaces are discussed and reviewed.

The deep web is an animal we cannot tame. It will continue to grow, and even though the general public is not yet familiar with it, as long as the surface web keeps getting censored and manipulated, more and more people will turn to the invisible web in search of freedom.