I've heard people talking about them before, but exactly what does it refer to? I think it refers to filing something on bugreport.apple.com; am I correct?
You can find out more at https://developer.apple.com/bug-reporting/ which states:
As it says, this tool replaces the older "bug reporter" which was sometimes known as "filing a Radar" because it created tickets in the system that Apple engineers know as Radar.You can now submit developer feedback and file bug reports to Apple using the native Feedback Assistant app for iOS and Mac, or the Feedback Assistant website. When you file a bug, you’ll receive a Feedback IDto track the bug within the app or on the website. Feedback Assistant replaces Bug Reporter, which is no longer available.