With many things happening throughout the internet, there is so much more in the www (world wide web) then it appears to be. The dark web is a part of the internet that is not visible to regular users.
To understand what the dark web is, you have to know what the deep web is. The deep web is a big network of websites that is not categorized by search engines.
The dark web is just a small part of the deep web. The deep web and dark web is just a place where illegal actions are performed without the other people such as police knowing.