Obviously, it depends on where you are.
Around here, BBQing is a generic term for anything cooked over coals outside. Most common is on a grill (covered or not) followed by smoking in a covered heat source.
Smoking or slow cooking is good for sitting around outside, drinking beer and tending to the cooking although it is very rarely looked at if you have controls and thermometers.
My friend does a lot of smoking/BBQing and in the case of big chucks of cow, pig, venison or moose, he starts it before going to bed with the right amount of chips in a pan in a electric grill that has good controls and is heavy. He looks at it somewhere in the early morning to add anything necessary and schedules it for afternoon eating.
Smoking of fish like salmon, whitefish is popular, but a little cooler, and some people check it by the calender instead of a clock(LOL).
If you get caught smoking a good fish like good, small walleye might get you arrested, but that is local tradition.