The Middle East (or, formerly more common, the Near East) is a region that encompasses southwestern Asia and Egypt. In some contexts, the term has recently been expanded in usage to sometimes include Afghanistan and Pakistan, the Caucacus and Central Asia, and North Africa. The history of the Middle East dates back to ancient times, and throughout its history, the Middle East has been a major centre of world affairs. The Middle East generally has an arid and hot climate, with several major rivers providing for irrigation to support agriculture in limited areas. Many countries located around the Persian Gulf have large quantities of crude oil. In modern times the Middle East remains a strategically, economically, politically, culturally and religiously sensitive region.