This is the total amount or quatity of goods and services that are available for sale to consumers at a specific period of time.

In economics, supply is the amount of something that firms, consumers, labourers, providers of financial assets, or other economic agents are willing provide to the marketplace. Supply is often plotted graphically with the quantity provided (the independent variable) plotted horizontally and the price (the dependent variable) plotted vertically. In the goods market, supply is the amount of a product per unit of time that producers are willing to sell at various given prices when all other factors are held constant. In the labor market, the supply of labor is the amount of time per week, month, or year that individuals are willing to spend working, as a function of the wage rate. In the financial market, the money supply is the amount of highly liquid assets available in the money market, which is either determined or influenced by a country's monetary authority.
Difference between stock and supply: Stock is the total amount of the commodity available with the producer. Supply is the only part of total stock which producers are willing to bring into the market and offer sale at particular price.

Supply Schedule:

A supply schedule is a table which shows how much one or more firms will be willing to supply at particular prices under the existing circumstances. Some of the more important factors affecting supply are the good's own price, the prices of related goods, production costs, technology and expectations of sellers. It is a tabular depiction of the relationship between the quantity supplied and the price of the goods represented graphically as a supply curve.

Supply Curve:

The supply curve is a graphical depiction of the supply schedule that illustrates that relationship between the price of a good and the quantity supplied.