The supply of a good or service is the amount that producers are willing to sell at given prices over a period of time.
Supply for a product shows us the relationship between its price and the quantity which will be sold by producers. Economic theory shows us that as the price increases for any good or service, the quantity supplied for that good should increase. This is commonly referred to as the law of supply.
The opposite also holds true: as the price of a good or service decreases, the quantity supplied should decrease.
The logic behind this relationship is simple: if the price of a good or services increases, producers can make more revenue from selling at a higher price. Therefore they are more motivated to sell so the quantity they are willing to supply to the market increases.
Icons made by Freepic from www.flaticon.com