The United Arab Emirates, sometimes simply called the Emirates or the UAE, is an Arab country in the southeast of the Arabian Peninsula on the Persian Gulf, bordering Oman to the east and Saudi Arabia to the south, as well as sharing sea borders with Qatar and Iran. The UAE is a federation of seven emirates (equivalent to principalities), each governed by a hereditary emir, who choose one of their members to be the president of the federation. The constituent emirates are Abu Dhabi, Ajman, Dubai, Fujairah, Ras al-Khaimah, Sharjah, and Umm al-Quwain. The capital is Abu Dhabi, which is also the state's center of political, industrial, and cultural activities. Islam is the official religion of the UAE, and Arabic is the official language. Since 1962, when Abu Dhabi became the first of the emirates to begin exporting oil, the country's society and economy were transformed. The late Sheikh Zayed, ruler of Abu Dhabi and president of the UAE at its inception, oversaw the development of all the emirates and directed oil revenues into healthcare, education and the national infrastructure. UAE oil reserves are ranked as the world's seventh-largest. It also possesses the world's seventh largest reserves natural gas resources and it is one of the most developed economies in Western Asia. Per capita income is the world's seventh-highest.