Step 1: Exchange.
The most basic feature of a market is the exchange of goods and services between buyers and sellers. Without exchange, there is no market.
Step 2: Competition.
Producers and sellers compete with each other to attract buyers, which improves quality and efficiency and controls prices.
Step 3: Price mechanism.
The forces of demand and supply determine the prices in the market. Prices act as signals to allocate resources and balance consumption and production.
Final Answer: \[ \boxed{\text{Exchange, Competition, and Price mechanism}} \]