Understand the distinction
Watts describe power; kilowatt-hours describe energy over time. A 1,000-watt device running continuously for one hour uses one kilowatt-hour. Real appliances can cycle or change power, so a nameplate calculation is not automatically a measurement of their actual use.
Put it in your home notes
Write both the quantity and its unit beside any comparison. A notebook labelled only “electricity” makes it easy to mix a momentary reading with a total. Use this distinction when reading an appliance specification, without treating its rated maximum as a prediction of your bill.