if you listen in on a microeconomics class chances are you'll hear the word marginal thrown around a lot in fact thinking on the margin is one of the most important parts of basic economics but what you ask does marginal mean economists will tell you that marginal means one more so instead of saying the marginal cost of margarine you could also say the cost of one more margarine since margarine is usually sold in units of one tub we would be talking about the cost of one more tub of margarine but let's say you have three tubs of margarine which one is the marginal margarine well the answer is the next one see in thinking on the margin economists are thinking about the cost or benefit of making a decision in this case buying a fourth tub of margarine then a fifth tub and so on for reasons that belong in their own video the marginal benefit tends to decrease as you go on and the marginal cost tends to increase if you graph the two together you see there will eventually come a point when the marginal cost equals the marginal benefit this is the the point that economists are interested in anywhere past this point and the costs are greater than the benefit so you're losing out anywhere before the point and you're not getting the greatest possible benefit and also losing out this is why marginal thinking is so important it allows economists to zoom in on specific decisions and tell how they should be made basically economics tells us that we should keep buying margine until its marginal cost equals its marginal benefit sounds tasty