Demand
Demand shows how much people will buy at each price.
About this topic
Demand is the quantity of a good that consumers are willing and able to buy at each price over a period. The law of demand says that as price rises, quantity demanded falls, and vice versa, all else being equal, so the demand curve slopes downward. The reasons include the substitution effect, where buyers switch to cheaper alternatives, and the income effect, where a higher price leaves less purchasing power.
Both willingness and ability matter. Wanting a sports car without the money is not demand. Demand matters because it tells firms what to produce and at what price, and it is half of how markets set prices.
A change in price causes movement along the curve, called a change in quantity demanded. A change in anything else shifts the whole curve, called a change in demand. Non-price factors include income, tastes and fashion, prices of related goods (substitutes and complements), population and expectations. For example, if the price of cinema tickets falls from 12 dollars to 8 dollars, more people go, a movement along the curve. If a popular film is released, demand itself rises at every price.
Misconception: students often mix up these two types of change. Another is thinking demand is a single number; it is a whole schedule or curve. Tip: ask whether the cause is the good's own price (move along) or something else (shift).
Key ideas
- Law of demand: higher price, lower quantity
- Demand curve slopes down
- Income and tastes shift demand
Quick check
Use cases: where Demand helps
- Homework: review the key idea behind Demand before you start a problem set.
- Exam revision: use the quick check to test whether you can recall Demand without notes.
- Visual learning: play with the interactive lab to see how Demand changes when you adjust its inputs.
- Teaching a friend: explain Demand in your own words, then compare your version with the key ideas.
Economics explains prices, jobs, budgets and government policy in daily life.
Frequently asked questions
What is Demand?
Demand shows how much people will buy at each price.
What will I learn in Demand?
Law of demand: higher price, lower quantity. Demand curve slopes down. Income and tastes shift demand.
Is Demand part of Economics & Money?
Yes. It is one of 30 Economics & Money topics on LearnViz HighSchoolEdu, with 3 key ideas, a live animation and a quick check.
Does the Demand lab work on a phone or tablet?
Yes. The animation resizes to fit your screen and supports touch, so you can drag, tap and slide with your finger.
How should I study Demand?
Read the summary and key ideas first, play with the interactive lab to see the idea in motion, then answer the quick check. If you get a question wrong, go back to the key idea it tests.
Do I need an account, and is my progress saved?
No account is needed. Marking a topic as learned is saved in your own browser, so it stays on that device and is not sent to a server.