The document discusses demand, including the definition of demand, demand schedules, the law of demand, determinants of demand, types of demand, individual and market demand curves, elasticity of demand, and changes in demand. Specifically, it defines demand as the quantity of a product consumers are willing and able to purchase at various prices. It also explains the law of demand, which states that demand is inversely related to price - as price increases, demand decreases, and vice versa. Additionally, it discusses factors that influence demand, such as income, price of related goods, and consumer expectations.