my favorite thing when I was a kid

We've learned a lot about octopuses (octopi? octopodes?) since I was a kid, but for a long time, they were my grade-school obsession. Here's a video on octopuses that tells me nothing new but is nevertheless fascinating.

Caution: The video claims the octopus has "nine brains," referring to the central brain and the eight nervous ganglia in its eight arms. But the ganglia, despite giving independence of action to each arm, can only loosely be called "brains" in their own right. 

I also learned an interesting little factoid: octopus arms are technically arms, not tentacles because of how the arms' suckers run along the limbs' entire length. Mollusks like squids have two tentacles (suckers only on the ends of the limbs) and eight arms. I didn't know any of this until I read about it just now. As the kids currently say, I was today years old when I found this out. In Korean, an octopus's limbs are miscalled "legs."