Supply is the amount of a product or commodity that is available.
In free market systems of economics, when supply is greater than demand, that results in oversupply and the price will usually begin to drop. In cases where demand is greater than supply a shortage will result and then prices will usually begin to increase.
Sometimes in business, supply is purposely restricted so that oversupply will not occur. The interrelationship between supply and demand is called supply and demand.
Shift in Supply - The supply curve is a simultaneous set of potential quantities offered at different prices, a positive relationship. A change in a factor other than price causes a supply shift, but the distinction between that and change in quantity supplied is not as fundamental as it seems.