Question for Facebook Experts

Hi,

I like to keep my business and personal life 100% separate when it comes to Facebook, and I don't like to bombard friends with content that I post for business purposes.

With that in mind, I've got a question about Facebook groups.

There are several closed groups relating to niches that I'm in which I would like to post to. However, I've always wondered if content posted to a closed group is ever visible to those who aren't members of the group. (I don't want to flood my friend's news feeds with my group posts).

I came across the following matrix on Facebook which only added to my confusion:

https://www.facebook.com/help/220336891328465

As you can see from the matrix, under "Who can see what members post," it says that for closed groups, only members can see posts.

However, the confusion comes in when you look under "Who can see stories about the group on Facebook (like in News Feed and search)?"

On this part of the matrix it says that Anyone can see stories. So, this leads me to the following questions:

1. What exactly does Facebook consider a "story?"

2. Can anyone tell me with certainty whether or not friends will see posts I make to closed groups, if they aren't members of these groups?

Thanks,

Dan