Within monopolistic competition sellers offer similar, but not standardized products for instance there are many shoe companies that offer buyers similar but different products. The market is monopolistic because each of the sellers has an influence over a small portion of the market with their products because they are not exactly alike. Some of the most distinguishing features are product differentiation and non-price competition are the most distinguishing features of monopolistic competition.
Within an oligopoly there are only a few sellers who offer a similar product. In an oligopoly there is less competition than that of monopolistic competition. In an oligopoly only a few large firms have a large percent of total sales in a market. An example of an oligopoly would be cereal companies because there are only a few options for buyers when they want to purchase a brand of cereal. Some characteristics are that there are few sellers and many buyers, more control of prices, little freedom to enter or exit the market.
A monopoly is defined as a singular unit that controls a portion of the market .
Natural monopolies occur when the prices are the lowest with only one producer. Meaning that this one producer has the lowest prices for this product or service and in some cases may be the only one providing it. An example of this would be operating systems that are available to the consumer.
Geographic monopolies occur their are no other producers or sellers in one particular area or region. Some examples of a geographic monopoly would be owning the only grocery store in a town, car service, gas station or hardware store in a town, forcing consumers to buy from them.
Technological monopolies are when a firm controls a manufacturing method, an invention or a type of technology. These types of monopolies occur when a corporation releases a lot of patents for a new method of manufacturing, an invention or a type of technology. With these patents the company is allowed to control their idea or technology because they are the only ones that have the rights to do so under their patents. Examples of this would be Instagram and Facebook.
Government monopolies occur when either the government owns the business or authorizes a business to be the only producer of a particular product or service.
Holt McDougal Economics: Concepts and Choices