In a pure market economy, there is absolutely no government interference, and products, pricing, and so on are completely determined by the marketplace and the private companies involved in it.

The economy of the United States has many elements of a market economy. Individuals and private companies are in charge of what is produced and how it is priced, and pricing fluctuates with supply and demand.

However, pure market economies do not actually exist in the real world. In the U.S., for example, there are governmental regulations to prevent monopolies and other aspects that might be harmful to the consumer. These would not exist in a pure market economy.