Discord is a VOIP application developed in 2015 as a replacement for Skype and Teamspeak servers, aiming itself primarily towards gamers although a good chunk of it's servers have nothing to do with gaming at all. The return of Ghost has seen the increased used of Discord servers versus traditional Skype and Tinychat rooms, and has already played an impact in several conflicts within the community, most notably being the TCR Cold War.
As far as chatrooms go, currently all known chatrooms besides TheBronyNetwork's Youtube stream chat and the TCR Steam Chat use Discord, including the private Inner Circle chatroom, which became a hotspot of drama following the recordings of the voice chat and screenshots of chat messages.
The Inner Circle Discord would later go on to win Best Chatroom at the Ghosties, and the TCR Discord would be awarded an honorable mention for Best Chatroom as well.
Ghost would go on to host his own Discord in February 2018.