I am pretty sure that Europe is often described as having free market, also it is often considered to be working pretty good, beside occasional shortcamings, definitely nothing like mass poverty. Altho I wonder what you you mean by capitalism, and why did you put quotes around free, do you think those markets aren't free, or what?

And what is capitalism, or communism, or socialism? I feel like there are different definitions of those things.

Not really, it is just length with adjustment for thermal expansion.