As said by Plexii, the supply and demand is what the consumer demand vs. what the suppliers are willing to supply.
When you see the chart seen, you would notice that there is a place that it meets and difference in the rest of the area.
If the supply is greater than the demand, the price would be a lot more lower. If however the demand is greater than the supply, the price would be higher. Using the graph, sellers can find out how to find the best profit through finding information on what buyers are willing to pay to buy their goods.
hope this helps
