Perfect competition :

Perfect competition is that situation in the market where there are large number of competitors of a product and none of the competitors has control over the price of the commodity. Price of the commodity is determined by the demand and supply of the commodity in the market. There are larger number of consumers in the market. Consumer can purchase a commodity from anywhere at the prevailing market price. It is hard to find any solid example of such a market situation. Nevertheless, we can say that we can purchase wheat and other cereals in the market at the prevailing market price and no individual producer has a control over this price Price of cereals is mostly determined by the forces of market demand and market supply. Economists consider a perfectly competitive market as an ideal market situation .

Monopolistic :

In real life, it is monopolistic competitive market that generally exists. It is that situation of the market wherein there are many sellers of the product, but the product of each seller is a bit different from the products of other sellers. This product differentiation shows itself in trade mark, name of the brand, quality differentiation or in different facilities and services offered to the consumers. There are many examples relating to this kind of market. Firms producing different brands of toothpaste, as Pepsodent, Colgate, Close-up, ete area operating under monopolistic competition.

Monopoly :

It is that situation of market in which there is a single seller of a product with no dose substitutes in the market. It is explained with the help of few examples:

Suppose, there is only one firm dealing in the sale of cooking gas in your town.In USA there are less examples In india , You get your electricity supply from one agency, that is Electricity Board; you can travel by railways owned, controlled and run by Government of India alone. All these are examples of monopoly. This situation of market, where a single (Mono) firm controls (Poly) the production of a commodity, is called Monopoly". Hence, monopoly is a market situation in which there is only one producer of a commodity with no close substitutes.

Oligopoly :

It is a form of the market in which there is a few big sellers of a commodity and a large number of buyers. Such seller has a significant share of the market. There is a high degree of interdependence among the sellers regarding their price and output policy. Because there are only a few sellers, price and output decision of one seller significantly impacts the price and output decision of other sellers in the market. Accordingly, there is a severe competition in the market (called cut-throat competition)

Example: There are only a few auto-producers in the Indian market. Maruti, Tata, Fiat, Ford and GM are some well known brand

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