Enable Topic and Post Filter

I'm sorry if this has been already asked and answered somewhere else. If so, could someone provide a link, please?

I've noticed that after today's fix, that there are two replacement options in My Preferences.

I seem to remember that I had "No Minimums" in that spot.

What exactly does it mean with the below options?

Enable Topic Filter: No Yes

Enable Post Filter: No Yes

What and how does it filter? I take it that it has something to do with collapsing topics.

I have both set for 'No' for now.