The online world, like the world in general, has a dark side, known as the “Darknet.” There lurks clandestine drug deals, illegal weapon purchases, money laundering, forged documents, child pornography, and even hitmen for hire.

One of the largest conduits to the Darknet was taken down by the FBI in 2013. It was called “Silk Road,” euphemistically named after a network of roads that facilitated trade in silk and other exotic goods between Europe and the East from the second century B.C. to the fifteenth century A.D., when shipping became more economical.

But the Darknet is still extant. Silk Road 2.0 went operational soon after the shutdown of the original Silk Road, then it too was shut down by the FBI. Soon after, another Darknet service, Diabolus Market, renamed itself Silk Road 3.0 to take advantage of the Silk Road’s name recognition.

Another conduit of the Darknet, The Pirate Bay, was taken down by Swedish police in December 2014. It was a place where you could find pirated software, music, films, TV shows, books, and other proprietary content, and it too has been replaced by similar services.

In the just-published book The Dark Net: Inside the Digital Underworld, author Jamie Bartlett talks in detail about such online criminality. The Darknet, he says, is a place “where users say and do what they like, often uncensored, unregulated, and outside of society’s norms. It is dark because we rarely see these parts of digital life, save the occasional flash of a sensational news report or shocking statistic.”

You won’t find any Darknet services through a Google search or by randomly clicking on links from other websites. To access it you need a special web browser called Tor, which began life as a project of the U.S. Naval Research Laboratory and which can be found online today.

Tor protects the identities of those using it and the sites browsed by repeatedly encrypting its activity with the help of a number of different network nodes around the Internet. Users buy the illegal goods and services using another service, Bitcoin, which also uses encryption to hide users’ identities.

Perhaps the most shocking service offered is called the Assassination Market. There are five explanatory instructions listed on the opening page: Add a name to the list, Add money to the pot in the person’s name, Predict when that person will die, Correct predictions get the pot, Making your prediction come true is entirely optional.

Needless to say, activities such as these illuminate the vilest aspects of human nature. Those involved in these activities often justify them with libertarian politics. They regard freedom to act as they please as the highest value, and they abhor any kind of government interference, oversight, or regulation.

Darknet marketplaces work much like legal marketplaces such as Amazon and eBay, says Bartlett, director of the Centre for the Analysis of Social Media, which is affiliated with the University of Sussex in England. User review systems identify those vendors who provide customers with the products advertised and good service and those who don’t.

Given that those involved in the Darknet regard themselves as being above the law, however, it’s not surprising that it’s easier to be scammed there and even have your identity stolen than at legal online marketplaces and ecommerce sites.

The decentralized nature of the Internet is what makes Darknet activities possible. There’s no “Internet Central.” From its beginning, the Internet was designed, initially by the U.S. Department of Defense, to be able to operate even if part of it goes down. Internet traffic just finds another way to get to its destination. As with any technological breakthrough, this can be both blessing and curse.

Tor and Bitcoin are used constructively as well. With Tor, people living in countries with oppressive governments can browse the Internet and post to discussion groups without fear of being prosecuted, imprisoned, or even killed. It can also be used for whistleblowing and news leaking. Tor, in fact, won the Free Software Foundation’s Award for Projects of Social Benefit in 2010. With Bitcoin, people living in developing countries who have little access to banks and other financial institutions can participate in online commerce.

In the concluding chapter of his book, Bartlett writes, “Transformative technologies have always been accompanied by optimistic and pessimistic visions of how they will change humanity and society. … Technology is often described as ‘neutral.’ But it could be more accurately described as power and freedom. … Power and freedom endow our creative and destructive faculties.”