Yes definitely. If the cost of an item is worth the same as the selling price, then you will not earn anything. Basically, the selling price already has the markup, so the selling price is definitely supposed to be higher than the cost of the item. For example, I bought a TV for 30 dollars. I would want to sell it at a selling price of 70 dollars. The difference of 40 dollars is my markup. The markup can also be expressed as a percentage if you divide the difference with the selling price.