POP QUIZ: What are Free Threads in the Threadpool

So here is the next trivia question for everyone.  If you have tried to change the Threadpool settings for .NET, you have seen the minFreeThreads and minLocalRequestFreeThreads settings.

What are those settings really used for?  What do they control or how do they limit things within the Threadpool?

For extra credit, when would be a time that you would want to change these from the defaults and how would you adjust them?

As always, I will wait until tomorrow to post any of the comments and will also post the answer.