is a tree or shrub in the genus Quercus
(/ˈkwɜrkəs/;Latin "oak tree"), having approximately 600 extant species. The common name "Oak" may also appear in the names of species in related genera, notably Lithocarpus
. The genus is native to the Northern Hemisphere, and includes deciduous and evergreen species extending from cool temperate to tropical latitudes in Asia and the Americas. The center of endemism is regarded as North America, particularly Mexico.