First. The deep web and dark web are two separate things. The deep web refers to the actual coding that makes shell programs work, like the actual programming of a web page. The coding used to archive and analyze data is called meta data. Big Data refers to the large scale collection and storage of metadata.
The dark web on the other hand is a place of intrigue and closely resembles poker in hell.
On the dark web is where you find websites that sell everything from grey market pharmaceuticals to organs. As one article once put it, it is a place of assassins, pedophiles, and drugs. Money or varying stand in currencies are traded illegally and legally here, and open source content and data are encouraged despite the desire for anonymity.
The dark web like all cultures developed over the years as a consequence of the evolution of the Internet, and is also where you will find mad scientists and engineering geniuses. DARPA has recently begun trawling the dark web to try and locate some of these geniuses.
My life strongly resembles a Weird Science graphic novel. I grew up online and my friends have always been a cultural hodgepodge of science people. So I’m very familiar with the dark web. The other day I read of a blogger I knew when he was a young teenager from Algeria; his virus made him internationally famous.