Linked from
The 21 pages that link to Watt, each with the reason it gives.
SI derived unitBroader topic: It expresses energy transferred per unit time.
Power (physics)Broader topic: It gives power a standard unit for comparing rates.
Kilowatt-hourBroader topic: The kilowatt-hour combines a kilowatt, or 1,000 watts, with an hour.
MKS unitsBroader topic: It expresses power from MKS units of energy and time.