The "dark net" and "dark web" connote a subset of secret websites that exist on an encrypted network.

Although the internet dominates most every facet of our daily lives at this time, it's important to remember that it has only been around for a few decades. While this is a relatively short span of time compared with the course of human history, it is a multitude of technological lifetimes. As such, the internet is an immensely vast place, a span of billions of individual sites that are connected to one another in a complicated combination of ways.

The most famous websites, like Facebook (FB), Google (GOOG) and Amazon (AMZN) are well known throughout the world. Besides those popular sites, there exists a much larger collection of less-traveled parts of the internet. And lurking beyond all of the basic, accessible areas of the internet are other pockets of sites. These last groups constitute the so-called "dark web" or "dark net."

'Dark Net' Versus 'Deep Web'

The terms "dark net" and "dark web" are occasionally used interchangeably but with subtle differences in meaning. They generally connote a subset of websites which exist on a network that is encrypted.

The fact that the network is encrypted means that it is not searchable by traditional means, such as a search engine, and it's not visible through traditional web browsers. Dark nets exist in many forms, and the term itself does not necessarily suggest any nefarious undertones. A dark net is any type of overlay network which requires specific authorization or tools to access.

Why might individuals wish to host websites on a dark net? Dark nets are commonly associated with a variety of different functions. They can be used for a number of crimes, including illegal file sharing, black markets, and as a means for the exchange of illegal goods or services. These are often the most highly-publicized uses of a dark net.

But they are also used for a host of other reasons. Dark nets are often called upon as a means of protecting political dissidents from reprisal, or as a tool for allowing individuals to circumvent censorship networks. They can facilitate whistleblowing and news leaks, and they can help to protect individuals from surveillance. As such, and because of the multitude of applications of a dark net, they are a hotly contested issue.

"Dark net" is commonly confused with "deep web." The deep web refers to unindexed sites which are unsearchable; in most cases, this is because those sites are protected by passwords. "Dark net" sites are purposefully hidden from the surface net by additional means. A large majority of internet sites constitute the "deep web," as they are password-protected.

The internet as compared to the "tip of the iceberg analogy." Indexed websites represent only 4% of the entirety of the web.

Encryption and the Dark Net

One of the common ways that dark nets are separated out from the surface net is through encryption. Most dark websites use the Tor encryption tool to help hide their identity.

Tor allows individuals to hide their location, appearing as if they are in a different country. Tor-encrypted networks require that individuals use Tor in order to visit them. Thus, those users' IP addresses and other identifying information is similarly encrypted. All of this combines to suggest that most anyone can visit sites on the dark net, so long as they have the proper encryption tools. But it can be incredibly hard to determine who created or oversees those sites. It also means that, if anyone participating in the dark net has his or her identity revealed, it can be dangerous.

Tor makes use of layers and layers of encryption, securing traffic by routing it through a dense network of secure relays to anonymize it. Tor is not illegal software in and of itself, in the same way that torrenting tools are not illegal. (See also: How Do BitTorrent Sites like The Pirate Bay Make Money?) In both cases, though, the software is commonly used to conduct illegal activity (either via the dark net or, in the case of torrenting tools, to download pirated material).

To put Tor's dark net links in context, it is useful to remember that Tor estimates only roughly 4% of its traffic is used for dark net services, with the remainder simply accounted for by individuals accessing regular internet sites with an increased level of security and anonymity.

Infamous Examples of the Dark Net

When most people think of the dark net, a few prominent examples come to mind. These are sites or networks of sites that have made headlines for one reason or another. Most are illegal for one or more reasons. However, there are other potential dark nets, and not all of them are necessarily illegal.

One of the most famous examples of a dark network was the Silk Road marketplace. Silk Road was a website used for the buying and selling of a variety of illegal items, including recreational drugs and weapons.

Silk Road was founded in 2011 and is often considered the first dark net market. Although it was shut down by government authorities in 2013, it has spawned a number of copycat markets.

Screenshot of the now shut down Silk road black marketplace.

Marketplaces such as Silk Road were instrumental in the development of cryptocurrencies, most of which rely on decentralization and enhanced security measures. The privacy and anonymity of many cryptocurrencies has made them the option of choice when completing transactions in dark net markets.

Reasons to Use or Avoid the Dark Net

Aside from illegal purchases and sales, there are legitimate reasons one might be interested in using the dark net. Individuals within closed societies and facing extreme censorship can utilize the dark net to communicate with others outside of their society. Even individuals within open societies may have some interest in using the dark net, particularly as concerns about government snooping and data collection continue to grow worldwide.

Nonetheless, a large portion of the activity which takes place on the dark net is illegal. It's not difficult to surmise why this might be the case: the dark net offers a level of identity security that the surface net does not. Criminals looking to protect their identities in order to evade detection and capture are drawn to this aspect of the dark net. For that reason, it's unsurprising that a number of notable hacks and data breaches have been associated with the dark net in some way or another.

In 2015, for example, a trove of user information was stolen from Ashley Madison, a website purporting to offer spouses a means of cheating on their partners. The stolen data showed up on the dark net, where it was later retrieved and shared with the public. In 2016, then-U.S. Attorney General Loretta Lynch cautioned that gun sales taking place over the dark net were becoming more common, as it allowed buyers and sellers to avoid regulations. Illegal pornography is another relatively common occurrence on the dark net.

Considering the nefarious underbelly of the dark net, it's no surprise that most individuals have no reason to access it. And yet, given the increased importance of cryptocurrencies in the financial world, it's possible that dark nets will become more of a feature for everyday internet users in the future. In the meantime, they may also still provide criminals a means of eluding capture, although true anonymity is never guaranteed, even when using encryption of the type found in these networks.

Investing in cryptocurrencies and other Initial Coin Offerings ("ICOs") is highly risky and speculative, and this article is not a recommendation by Investopedia or the writer to invest incryptocurrencies or other ICOs. Since each individual's situation is unique, a qualified professional should always be consulted before making any financial decisions. Investopedia makes no representations or warranties as to the accuracy or timeliness of the information contained herein. As of the date this article was written, the author owns cryptocurrencies.

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