The "deep web" is the part of the internet that is hidden from regular search engines.
There are several names for the "deep web." Some refer to it as the "dark web"; others, the "invisible web," but all refer to the parts of the internet not accessible via generic browsers like Google, Bing and Firefox. Instead, those curious enough must download a deep web browser like Tor. The concept of the deep web rose to mainstream prominence with the Silk Road trial back in 2015, where Silk Road founder Ross Ulbricht was sentenced to a double life sentence plus forty years. The Silk Road was an online deep web marketplace that introduced many internet users to Bitcoin, as Bitcoin was the main currency used on the site.
Despite the FBI’s crackdown on the Silk Road, the deep web continues to be a popular destination for those seeking what they cannot find within the confines of the traditional internet. Traditionally the deep web is associated with the purchase and sale of drugs, illicit goods and other black market commodities.