The Dark Web is the part of the World Wide Web (and associated services) that is hidden. You won’t find these sites on Google or other search engines because they have never been registered  and deliberately don’t have links from other sites that Google or the other search engines know about.  The only way to find these sites is to be given the relevant Internet address. i.e. URL. And usually a login and password or encryption required.

Much of this is to cover illicit and/or illegal activity such as fraud, phishing, terrorist activities, hacking etc.

However, there is also a lot of activity on the Dark web that people don’t want to be seen but is not illegal such as whistle-blowers preparing or sharing information, things that are legal in some jurisdictions but not in others, unmonitored communication in countries with totalitarian controls etc. 

The Dark Net is comprised of Tor, I2P and similar networks plus many peer to peer networks .

Dark Net websites are accessible only through networks such as Tor and I2P ("Invisible Internet Project"). Tor browser and Tor-accessible sites are widely used among the Dark Netusers and can be identified by the domain ".onion".

Tor was created by the U.S Navy and focuses on providing anonymous access to the Internet. I2P specialises in allowing anonymous hosting of websites. Using these technologies means that the Identity and location of a Dark Net user cannot be tracked.  

The Dark Net encryption technology routes users' data through a series of  servers each of which encrypt the message thus adding layered encryption and making it virtually impossible to decrypt.  

Due to this complicated system, websites are not able to track geolocation and IP of their users and the users are not able to get this information about the server.

 

Communication between Dark Net users is thus highly encrypted allowing them to talk, blog, and share files confidentially.

Web Based Hidden Services

The biggest uses of the Dark Web according to a 2016 study by researchers at King's College London are:-

Drugs, markets, fraud, Bitcoin, email, whistle-blowers, counterfeiting and online anonymity.

These include the following:-

Botnets

Botnets are networks of controlled computers that can be used to attack a website – causing service interruptions or even crashes.. Botnets are often controlled from the Dark Web and can be rented for use via the Dark Web.

Bitcoin services

These services convert money into Bitcoins or vice versa and are sometimes used as a way of laundering money.

Dark Web Markets

Commercial Dark Web markets such as Silk Road have become famous as the illegal equivalent to Amazon, giving people access to buy and sell drugs, guns, secrets, software viruses and more.   Silk Road was taken down by the authorities in 2016 but has been replaced by numerous smaller markets on the dark web.

Other markets sell malware and software tools, weapons and much more. Research into the quality of products advertised compared to their actual quality shows some products do match but for illegal drugs usually the product is much poorer quality than advertised.

Hackers

Many hackers sell their services there individually or as a part of groups such as  xDedic and hackforum,

Hacking tools of all possible kinds are available for sale on the Dark Markets. People can buy kits for carrying out Phishing attacks on a large scale.

Fraud

There are many fraud based services available as people offer the techniques and software tools necessary for various kinds of fraud.   

Phishing and scams

There are endless scam and phishing Dark Web sites . Many such sites are themselves scams. If you’re defrauded on the Dark Web trying to buy something illegal – you can’t exactly complain to the Police.   

Terrorism

There are at least some real and fraudulent websites claiming to be used by ISIS. In the wake of the November 2015 Paris attacks an actual such site was hacked by an Anonymous affiliated hacker group GhostSec and replaced with an advert for Prozac. The Rawti Shax Islamist group was found to be operating on the dark web at one time.

The Dark Net is a dangerous place.