Everybody who uses Reddit knows the system of up voting and down voting. Facebooks philosophy was always to stay positive and they know the dangers of cyberbullying, but now they are testing a down vote button.
When they reformed there like button into the well know funny, sad, like, … button they didn’t want to make a dislike button, fearing that some people would use it with the wrong intentions. But now they are trying to make a system where you can down vote comments.
You can compare it with the Reddit down vote, but they went further. They still hold on to their philosophy, which is a great thing. So they took it a step further, if you down vote a comment you will have to give feedback why you did that.
The main reason for this down vote is to get harmful comments don’t get in the way of meaningful comments. For the moment they are trying it on a small public in the US, but it is meant to become a worldwide feature.