The deep sea is the deep ocean beneath the oceans crust, where organisms live and evolve.
It is where we live, breathe, eat, breathe and breathe, and where we spend the majority of our time.
It contains a diverse array of marine life, including sharks, octopus, whales, fish, squid, squid-like creatures called crustaceans, and crustacean-like organisms called fish.
Some of the most interesting species in the deep sea include the deep bluefin tuna, which is thought to be the deepest bluefin in the world, at more than 4,300 metres (16,500 feet).
There are some more exotic creatures, including the giant manta ray and the hammerhead shark.
Here are a few things you might not know about the deep-sea fishing license: deep sea fisherman are required to apply for a deep-water fishing license if they want to fish in the ocean.
The license covers the deepest depths of between 50 and 1,000 metres (165 and 595 feet).