Class 11 Micro Economics Notes · CBSE

Meaning of Supply

Meaning of Supply — understanding what supply is, its four essential elements, and how supply differs from stock. CBSE Class 11 Microeconomics notes with the sugar example.

Last updated: 16 Sep 2026

Notes

Special Features of Supply

Like demand, supply is also expressed as a relationship between price and quantity. Before proceeding with the meaning of supply, it is important to understand some special features of supply:

Supply is a desired quantity

It indicates only the willingness — how much the firm is willing to sell and not how much it actually sells.

Think of a street vendor deciding each morning how many notebooks to put on display. The number he decides to display is his supply — not how many he actually sells by evening.

Supply does not comprise the entire stock

It indicates the quantity the firm is willing to bring into the market at a particular price.

Samsung may have 10,000 TV sets in its warehouse, but if it decides to offer only 6,000 in the market at the current price, the supply is 6,000 — not 10,000.

Supply is always expressed with reference to price

Just like demand, supply of a commodity is always at a price, because with a change in price the quantity supplied may also change.

A chai stall owner supplies 80 cups at ₹10 each, but is willing to supply 120 cups if the price rises to ₹15 — supply changes with price.

Supply is always with respect to a period of time

Supply is the quantity the firm is willing to supply during a specific period of time (a day, a week, a month or a year). Due to this reason, supply is a 'Flow Variable'.

⭐ A farmer does not say "I will supply 50 kg of wheat" — he says "I will supply 50 kg per week." Supply only makes sense with a time dimension.

Definition of Supply

Supply

Supply refers to the quantity of a commodity that a firm is willing and able to offer for sale at a given price during a given period of time.

The definition of supply highlights 4 essential elements ⭐:

1Quantity of a commodity

2Willingness to sell

3Price of the commodity

4Period of time

Individual Supply and Market Supply

Like demand, supply can also be either for a single seller (Individual Supply) or for all the sellers (Market Supply).

Individual Supply

Individual Supply refers to the quantity of a commodity that an individual firm is willing and able to offer for sale at a given price during a given period of time.

Market Supply

Market Supply refers to the quantity of a commodity that all the firms are willing and able to offer for sale at a given price during a given period of time.

Supply vs Stock

The term 'supply' is often confused with 'stock' of the commodity. However, in economics, the two terms are different.

Stock

Stock refers to the total quantity of a particular commodity that is available with the firm at a particular point of time.

Stock can never be less than the supply. Example: if a seller has 50 tonnes sugar in his godown and he is willing to sell 30 tonnes at ₹37 per kg, then supply is 30 tonnes and stock is 50 tonnes.

Supply vs Stock
Aspect	Supply	Stock
Meaning	Quantity of a commodity that a firm is willing and able to offer for sale at a given price during a given period of time.	Total quantity of a particular commodity that is available with the firm at a particular point of time.
Nature	A flow concept — it relates to a period of time.	Not a flow concept — it relates to a particular point of time.
Relation to price	Always related to price of the commodity — it changes with change in price.	Not related to price — it indicates a fixed quantity.

Key Takeaways

Supply is the quantity of a commodity a firm is willing and able to offer for sale at a given price during a given period of time. ⭐
Supply is a desired quantity — it shows willingness to sell, not what is actually sold.
Supply is a flow variable — always expressed with respect to a period of time. ⭐
The four essential elements of supply are: quantity, willingness to sell, price, and period of time. ⭐
Individual supply is one firm's supply; market supply is the supply of all firms.
Stock is the total quantity available with the firm; supply is only the part brought to market — stock can never be less than supply. ⭐