By that I mean, is the scope of this site solely the way a user interacts with software on their screen (monitor, touch screen, smart phone, etc)? Or does it include the way a user interacts with... anything?
For example, would a question regarding the layout of buttons and LEDs on an embedded device be off topic? Or the controls on a DVD player? Or when to use actual depressable buttons vs those lighted, pressure sensitive parts of a device?
I don't necessarily expect a "user interface" SE to attract people designing physical devices, but if it did -- is that on-topic?