demand changes when people's incomes change

demand changes when the prices of substitutes and complements change

the quantity demanded changes when the price of the good changes

the price of the good changes when people's demand for the good changes

increase in demand

decrease in demand

market size

price of a substitute good

price of a complementary good

tastes and preferences 

movement along the curve

movement along the price curve

change in quantity demanded of a good

shift in the demand curve

quantity demanded increases

quantity demanded decreases

demand increases

demand decreases