Globalization can be considered as a system of flows:
- Freight (trade). Mainly asymmetrical flows taking place to satisfy material demands ranging from raw materials to finished goods and all the intermediate goods in between. The asymmetry is reflective of trade imbalances as well as the general linear organization of supply chains (upstream to downstream). Flows are mainly supported by maritime shipping with port infrastructures acting as the main gateways of this flow system, but airports play an important role in the trade of high-value goods. Trade networks are organized as interconnected hub-and-spoke structures along the main poles of the global economy.
- Passengers (migration). Mainly symmetrical flows of people taking place for a variety of reasons, most of them related to tourism with air transportation being the dominant mode supporting such flows. The global air transport system can handle about four million passengers per day and is organized as interconnected hub-and-spoke networks converging around major airports.
- Information (telecommunications). The complex and extensive flows of information used for communication, power exchanges (e.g. an online order), and symbolic exchanges (e.g. education). Information flows can both take a physical (e.g. parcels) and non-physical form, which are dominantly articulated by a network of global cities. While communication flows are mostly symmetrical, power and symbolic exchanges are asymmetrical (from the information provider to the consumer of information).