A more thorough explanation:

Definition: Traffic refers to the exchange of goods, commodities, or money between people. It can also refer to the movement of people, animals, vehicles, and vessels along a transportation route.

Examples:

• John is in the business of trafficking illegal drugs.
• The traffic of goods between countries is an important part of the global economy.
• The traffic on the highway was heavy during rush hour.
• The traffic of ships in the harbor was monitored by the coast guard.

The first example illustrates the illegal trade of drugs, which is a form of trafficking. The second example shows how traffic can refer to the exchange of goods between countries. The third example demonstrates the movement of vehicles along a transportation route, while the fourth example shows the movement of vessels in a harbor.