substitutes- demand for a brand or product type can be affected by the price change so if cheaper demand goes up
complementary products - when one good is bought with another e.g. printer and ink and if ink was to increase in price than printers demand would decrease
consumer income- higher disposable income means more money available to spend on other things leading to a increase in demand for expensive products
fashion consumer tastes- changing trends affect demand as consumers want new stuff eating too much sugar is a danger leading to fizzy drinks demand decreasing
advertising and branding- aims to increase demand for a product or encourage exisiting customers to be loyal
demographics- age, gender, ethnicity etc all have an impact on demand
seasonal changes- some goods are only sold at certain times of year such as Christmas cards and chocolates leeadign to the demand of them increasign n that time period
external shocks- if there is flood the demand for sandbags would increase to protect homes