A cappella is a kind of musical performance in which no instruments are used other than human voices and other body parts. There are quite a few excellent a capella groups, but one of the most astounding, to me at least, has been one that originated right near where I live: Pentatonix! Specifically, they hail from Arlington, Texas.

This was the first video of theirs I saw:

Being a typical guy, I paid more attention at first to the beautiful girl than the others. But that would not last long, because then I saw THIS:

WOW! And then I saw this, which proved they could do just about anything:

And here is a collection of facts about them:

Here is their Facebook page:
https://www.facebook.com/Pentatonix/

I think I will be paying much more attention to these people over the next few years.