Aquaman is the current King of the ocean. Originally born to a human father, and a mother who died after birth, Aquaman learned to live under water through reading ancient Atlantean books in the underwater dome that his father built. Later, Aquaman is told to have been born to an Atlantean mother, so Aquaman is not entirely sure of exactly what his origin story is, or where he belongs in this world, or who he even really is. Regardless of where he came from, Aquaman possesses super human strength, the ability to telepathically communicate to the ocean creatures, and super swimming abilities. Aquaman's cover identity is Michael Phelps, using his extraordinary swimming abilities to earn him a multitude of swimming awards, including gold medals in the past Summer Olympics. Whenever the media pokes into his recreational pot use and/or abuse of his natural swimming prowess, Aquaman retreats to his secondary base, located in the the underwater city of New Venice. His half-brother, Orm, grew up to resent him and became his arch nemesis the Ocean Master.
Aquaman sometimes leads the Justice League when everyone else is own vacation. Fortunately for him, his toughest battle was only when the Martians from Mars attacked.
Watch Aquaman face his arch nemesis, Ocean Master here