Complementary Goods: Complementary goods are products that are typically used together with another good. When there's an increase in demand for one good, it often leads to an increase for its complementary good as well.
Substitute Goods: Substitute goods are products that can be used as alternatives to each other. An increase in demand for one substitute good often leads to a decrease in demand for its substitute.
Consumer Income: Changes in consumer income can affect the demand for certain goods. When income increases, consumers may have more purchasing power and be willing to buy more of a product.