Railroad: A system of tracks that trains run on, enabling transport of goods and people across long distances.

Transcontinental Railroad: A railway that connected the eastern and western parts of the United States, completed in 1869.

Consolidation: The process of merging smaller companies into larger corporations to control more of the market.

Standard Gauge: The uniform width of railroad tracks, which allowed trains from different companies to run on the same tracks.

Growth of Industry: The rapid increase in manufacturing and transportation during the late 19th century, driven by innovations like railroads.

Gilded Age: The period in the late 1800s characterized by economic growth, industrialization, and often, corruption.

Labor Impact: The effect of railroad construction and operation on workers, including working conditions and employment opportunities.

Economic Impact: How railroads facilitated trade, expansion, and economic growth across the United States.

Social Change: The influence of railroads on American society, including migration patterns and urbanization.