The deep web is the part of the internet that is not indexed by conventional search engines. It is estimated that the deep web is 500 times larger than the surface web, containing a wealth of information and services that can be accessed with specialized software. While some of the websites on the deep web are illegal, many are legitimate and provide a wide range of services and information.

The most popular websites on the deep web include The Hidden Wiki, a comprehensive list of links to hidden services and websites; Tor Search, an unindexed search engine for the deep web; TorMail, an anonymous email service; and The Pirate Bay, a website that provides access to a variety of digital content. Other popular websites on the deep web include the Silk Road, an online marketplace for buying and selling illegal goods; Ahmia, a search engine for hidden services on the Tor network; and Torbook, a social networking site similar to Facebook.

In addition to these websites, there are many others that are popular on the deep web, including online forums, marketplaces, and peer-to-peer file sharing networks. With the right software and access, anyone can explore the deep web and find out what it has to offer.