From Facebook to Instagram to Twitter, my social-media feeds have been flooded with selfies next to famous artwork.

The selfies are seemingly parallel in nature to the artwork.

You probably know what I'm talking about. These things:

Avery Hartmans, thief of heartsAvery Hartmans

As it turns out, all those photos are from a Google app that's over a year old. It's called the Google Arts & Culture app, and it's free on Google Play and the Apple App Store.

But the ability to compare your face to famous works of art is a new feature. And it's one that's clearly caught on. You may be wondering how to use it, and I'm here to help with that.