When people refer to a whirlpool hot tub spa, spa or whirlpool – are they all talking about the same thing? Or are they something different? Here is a brief look at the history of the modern day hot tub and the names we use to describe them. Hot Tubs. The term hot tub originally referred to the wooden, barrel shaped tubs, which became popular in the late 1960’s and early 1970's. Based on ancient..