sea star or star fish? (California)

I overheard a discussion last night between two friends about whether one should call these animals “sea stars” or “star fish”since they're not really fish. I like the idea of accuracy in naming for sure. In any case, this postcard arrived from our own dear Pinot who was vacationing in Monterey while we were off on the East Coast. He wrote:

“Dear Bà & Daddy, I am having a very good time at camp. There are lots of good smells here. Mira is a great buddy. I get treats for just being a pretty boy, too! Pinot (wet kisses too)”