Professor Inkling Octopus is the founder of the Octonauts. He's a creature known as a Dumbo Octopus and he has a deep understanding about marine life. Inkling founded the Octonauts to promote marine research and preservation. Aside from being their founder, Inkling is also their oceanography professor. However, he rarely ever goes out on missions because of his delicate big brain. Instead he prefers to help the team from his library in the Octopod. However, Professor Inkling showed his physical prowess when connected to the Octopod to combat The Colossal Squid.
Unlike the other Octonauts, Professor Inkling (along with vegimals) is an amphibious creature. He is capable of breathing in and out of the water. But, like Captain Barnacles, he also possesses certain attributes pertaining to his species. He admits being able to squirt ink for protection, and has little suckers on his tentacles for him to move and climb.
Inkling is almost always in his 3 chairs: his small chair in H.Q., his large can in the launch bay, and his chair in his library. He will sometimes walk around though, but it isn't seen quite often.
Just like Tweak, who sleeps where she works, it's believed that the same can be said for Inkling. He too appears to live and sleep where he works, which is the Octopod library. He is apparently the oldest octonaut, judging by the monocle.