Afghans have both common cultural features and those that differ between the regions of Afghanistan, each with distinctive cultures partly as a result of geographic obstacles that divide the country. Family is the mainstay of Afghan society and families are often headed by a patriarch. In the southern and eastern region, the people live according to the Pashtun culture by following Pashtunwali (the Pashtun way). Key tenets of Pashtunwali include hospitality, the provision of sanctuary to those seeking refuge, and revenge for the shedding of blood. The Pashtuns are largely connected to the culture of Central Asia and the Iranian Plateau. The remaining Afghans are culturally Persian and Turkic. Some non-Pashtuns who live in proximity with Pashtuns have adopted Pashtunwali in a process called Pashtunization, while some Pashtuns have been Persianized. Those who have lived in Pakistan and Iran over the last 30 years have been further influenced by the cultures of those neighboring nations. The Afghan people are known to be strongly religious.