Final answer:
The sum of all individual demand curves for a good is known as market demand. It shows the total quantity demanded of a good at different prices, capturing the aggregated purchasing preferences of all consumers in the market.
Step-by-step explanation:
The sum of all individual demand curves for a good is called market demand. The concept of market demand reflects the total quantity of a good or service that all consumers in the market are willing to purchase at various prices. It is derived by horizontally summing the individual demand curves of all consumers in the market, representing the aggregation of their preferences and purchasing power at different price points.
As price increases, the quantity demanded typically decreases, which is known as the law of demand. Factors that can shift the demand curve include changes in consumer preferences, income, prices of related goods, expectations, and the number of buyers. These shifts reflect changes in the quantity demanded at every price point, illustrating how market conditions and consumer choices impact market demand.