Stagflation is a combination of stagnant economic growth, high unemployment and high inflation.

(i) The value of the monetary unit is directly linked with a certain weight of gold.
(ii) The purchasing power of a unit of money is maintained equal to the value of a fixed weight of gold.

(i) Money is, what money does - Walker:
(ii) Money can be anything that is generally acceptable as a means of exchange and at the same time acts as a measure and a store of value. - Crowther.

(i) It is the slowing down the rate of inflation by controlling the amount of credit (bank loan, hire purchase) available to consumers without causing more unemployment.
(ii) It is defined as the process of reversing inflation without creating unemployment or reducing output in the company.

(i) On the basis of speed there are four types of inflation - Creeping inflation, Walking Inflation, Running inflation, Galloping inflation.
(ii) Demand-Pull inflation, Cost-Push inflation.
(iii) On the basis of inducement - currency inflation, credit inflation, deficit induced inflation, profit induced inflation, scarcity induced inflation, tax induced inflation.

(i) After the barter system and commodity money system, modern money systems evolved.
(ii) Metallic standard is the premier one.
(iii) Some kind of metal, gold or silver is used to determine the standard value of the money and currency.
(iv) Standard coins made out of the metal are the principal coins used under the metallic standard.
(v) These Standard coins are full bodied or full weighted legal tender.
(vi) Their face value is equal to their intrinsic metal value.

Boom or Prosperity:
1. The employment and the movement of the economy beyond full employment is the characterized features of boom.
2. There is hectic activity, money wages rise, profits increase, interest rates go up, demand for bank credit increases.
3. There is all round optimism.
Recession:
1. The turning point from boom condition is recession.
2. Failure of a company or bank brings a phase of recession.
3. Investments are drastically reduced, production falls, income and profits decline.
4. There is panic in the stock market and business is dull.
5. Liquidity preference of the people rises and money market becomes tight.
Depression:
1. The level of economic activity becomes extremely low.
2. Firms incur loss and close down resulting in unemployment.
3. Interest rate, profits, wages are low.
4. Agricultural class and wage carners are badly affected.
5. Banks do not lend to businessmen.
6. The extreme point of depression is called as "trough".
7. Keynes said that autonomous investment of the government can help the economy to come out of depression.
Recovery:
1. After depression, recovery sets in the upswing.
2. It begins with the revival of demand for capital goods.
3. The demand slowly picks up and in due course there is more production, profit, income, wages and employment.
4. Recovery may be initiated by innovation or investment or by government.

Introduction:
(i) It was first propounded in 1588 by an Italian economist Davanzatti. It was popularised by an Americill economist, Irving Fisher is his book, "The Purchasing Power of Money" in 1911. He gave it a quantitative form in terms of "Equation of Exchange".
Equations:
MV = PT
(i) The Supply of Money = Demand for Money
M = Money Supply
V = Velocity of Money
P = Price level
T = Volume of Transaction.
(ii) The total quantity of money will be equal to the total value of all goods and services bought and sold.
\(P=\frac{M V}{T}\)
(iii) The quantity of money determines the price level and the price level varies directly with the quantity of money provided 'V' and 'T' remain constant.
(iv) Later Fisher extended his exchange to include bank deposits M₁ and its velocity V₁.
\(P T =M V+M^{\prime} V^{\prime} \)
\(P =\frac{M V+M^{\prime} V^{\prime}}{T}\)
- The price level is determined by
(a) quantity of money in circulation M
(b) velocity of circulation of money V
(c) volume of bank credit money M₁
(d) velocity of circulation of credit money V₁
(c) Volume of trade ('T')

(i) It show's the effect of changes in the quantity of money on the price level.
(ii) When quantity of money is OM₁, the price level is OP₁.
(iii) When the quantity of money is doubled to OM₂, the price level is also doubled to OP₂.
(iv) When quantity of money is increased four-fold to OM₄, the price level also increases by 4 times to OP₄ his relationship is shown by the curve OP = f(M) from the origin at 45^o.
Quantity of money
(i) Fig B shows the inverse relation between the quantity of money and the value of money.
(ii) Value of money is taken on the vertical axis.
(iii) When the quantity of money is OM₁, the value of money is OI / P₁.
(iv) When quantity of money is doubled to OM₂, the value of money becomes one half of what it was before (OI / P₂)
(v) When quantity of money increases by the four fold to OM₄, the value of among is reduced by OI / P₄
(vi) This inverse relationship between the quantity of money and the value of money is shown by downward sloping curve 1 / OP= f(M).