To experienced mixers, this is very obvious but to beginners it's not always easy to see why they will help you.
I'm also trying to make a case for why and how you can use them. I quickly start by showing how the technique is carried out by routing audio from individual channels such as a Kick, Snare and Hi Hat to a group channel called "Drum Bus" In this video I show a quick and simple way to create and use Bus or Group channels in the mixer on FL Studio 12.