Transportation infrastructure in the context of "Train station"

A global city (also known as a power city, world city, alpha city, or world center) is a city that serves as a primary node in the global economic network. The concept originates from geography and urban studies, based on the thesis that globalization has created a hierarchy of strategic geographic locations with varying degrees of influence over finance, trade, and culture worldwide. The global city represents the most complex and significant hub within the international system, characterized by links binding it to other cities that have direct, tangible effects on global socioeconomic affairs.

The criteria of a global city vary depending on the source. Common features include a high degree of urban development, a large population, the presence of major multinational companies, a significant and globalized financial sector, a well-developed and internationally linked transportation infrastructure, local or national economic dominance, high quality educational and research institutions, and a globally influential output of ideas, innovations, or cultural products. Global city rankings are numerous. New York City, London, Tokyo, and Paris are the most commonly mentioned.

The transport/transportation and logistics industry is a category of companies that provide services to transport people or goods. The Global Industry Classification Standard (GICS) lists transport below the industrials sector. The sector consists of several industries including logistics and air freight or airlines, marine, road and rail, and their respective infrastructures. Entire stock market indexes focus on the sector, like the Dow Jones Transportation Index (DJTA).

In the EU, the transport industry directly employs around 10 million people and accounts for about 5% of the gross domestic product (GDP). Logistics account for 10–15% of the cost of a finished product for European companies. On average 13.2% of every household's budget is spent on transport, which still depends heavily on fossil fuels and represents an important source of CO₂ emissions. Emissions from road freight transport have risen by more than 20% since 1995, counterweighting the increased energy efficiency of vehicles.

The United States has a highly developed diversified market-oriented mixed economy. It is the world's largest economy by nominal GDP and second largest by purchasing power parity (PPP). As of 2025, it has the world's ninth-highest nominal GDP per capita and eleventh-highest GDP per capita by PPP. According to the World Bank, the U.S. accounted for 14.8% of the global aggregate GDP in 2024 in purchasing power parity terms and 26.2% in nominal terms. The U.S. dollar is the currency most used in international transactions and the world's foremost reserve currency, backed by a large U.S. treasuries market, its role as the reference standard for the petrodollar system, and its linked eurodollar. Several countries use it as their official currency and in others it is the de facto currency. Since the end of World War II, the economy has achieved relatively steady growth, low unemployment and inflation, and rapid advances in technology.

The American economy is fueled by high productivity, well-developed transportation infrastructure, and extensive natural resources. Americans have the sixth highest average household and employee income among OECD member states. In 2021, they had the highest median household income among OECD countries, although the country also had one of the world's highest income inequalities among the developed countries. The largest U.S. trading partners are Mexico, Canada, China, Japan, Germany, South Korea, the United Kingdom, Taiwan, India, and Vietnam. The U.S. is the world's largest importer and second-largest exporter. It has free trade agreements with several countries, including Canada and Mexico (through the USMCA), Australia, South Korea, Israel, and several others that are in effect or under negotiation. The U.S. has a highly flexible labor market, where the industry adheres to a hire-and-fire policy, and job security is relatively low. Among OECD nations, the U.S. has a highly efficient social security system; social expenditure stood at roughly 30% of GDP.

A transportation authority, transportation agency, or transportation department is a government agency that regulates, manages, or administers transportation-related matters, such as roads, transportation infrastructure, traffic management, or traffic code.

Transportation authorities go by a number of names, such as "department of transportation" or "ministry of transport", among others. They often manage other government agencies that oversee specific fields of transportation, such as civil aviation authorities, highway authorities, logistics regulators, rail transport regulators, maritime transport regulators, and transportation safety boards.