The demand relationship can also be expressed as a diagram, with the price on one axis and the quantity demanded on the other axis. Conventionally, in economics, we put the price on the vertical axis, and the quantity demanded on the vertical axis. This diagram will usually take the form of a line or curve. We usually call it "the demand curve" (even when it is a straight line).
Here is a "demand curve" of the demand for beer in 1960, based on the estimated numbers from the previous page.
Terminology
