How does gross domestic product (gdp) differ from gross national income (gni)?

GDP measures the money that a country makes in its own land, while GNI measures the money it makes in other countries and at home.

the romans were initially interested in expansion via sicily (which at that time was a cultural melting pot), part of which lay under carthaginian control. at the start of the first punic war (264-241 bc), carthage was the dominant power of the western mediterranean, with an extensive maritime empire