I assume you’re talking about the one found in samsung phones. It’s basically like a launcher with shortcuts to apps you can access from any screen without having to go back to home or the app tray. Personally I found it to be too much also, not very customizable and inefficient use of space with only a few apps showing up there. It can be disabled in settings.
I like the idea though. I use the one handed+ module in goodlock where I can set another more compact app launcher when I diagonally swipe down from anywhere along the right edge screen. I have other shortcuts set to other gestures. It’s handy for multitasking.