In political science it is general regarded as such: States are self-governing political entities with a basis from the Treaty of Westphalia (thus the term the Westphalian System for state sovereignty and interaction). Nations however are groups of people sharing common descent, history, culture, or language and often have long term habitation in a certain territory. There can be nations within a state (Former Yugoslavia had several, along with several modern middle eastern and African countries) and states within a nation (North and South Korea, previously Vietnam). When the two are together it is a Nation State (France, Germany, etc) were the state is comprised of citizens or subjects that are relatively homogeneous in language or common descent. State is general the used interchangeably with country, through so time in error.