The state of Yap is one of four states made up of separate groups of islands that comprise the Federated States of Micronesia (FSM). The islands of the FSM stretch out over 1,678 miles in the western Pacific Ocean.
There are over 100 land masses in Yap State, but only 22 of its islands are inhabited. The main island group of Yap, called Yap Proper, is located north of the equator, 640 miles south of Guam. The other states of the FSM are Pohnpei (the capital state), Kosrae and Chu'uk (formerly known as Truk). Yap is the most traditional of the four distinct societies of the FSM.
The FSM is a sovereign nation with its own constitution. Under the provisions of the Compact of Free Association, a treaty adopted in 1986 between the FSM and the United States, the U.S. is responsible for the defense of the FSM. It also funds a wide range of other government services, including the postal service, building and maintenance of basic infrastructure, and agricultural, economic development and social programs.
Together, the states comprise around 607 islands, a combined land area of approximately 702 km2 (271 sq mi), covering a longitudinal distance of almost 2,700 km (1,678 mi) just north of the equator. They lie northeast of New Guinea, south of Guam and the Marianas, west of Nauru and the Marshall Islands, and east of Palau and the Philippines.
While the land area is quite small, FSM covers more than 2,600,000 km2 (1,000.000 sq mi) of the Pacific Ocean, an area comparable to that of Argentina.
The FSM was formerly a part of the Trust Territory of the Pacific Islands, a United Nations trust Territory under U.S. administration.
It formed its own constitutional Government on May 10, 1979. After independence on November 3, 1986, it became a sovereign state, under the Compact of Free Association with the United States.
The administrative center of the FSM is Palikir, Pohnpei, which is also the capital of the FSM.
Chuuk State is by far biggest state in the FSM, with a surface area of 420 km2 (1,088 sq mi) and a population of about 54,600 people. It is followed by Pohnpei State, with a surface area of 345 km2 (133.2 sq mi) and roughly 34,700 people, Yap State with a land area of 118 km2 (45.6 sq mi) and roughly 16,400 people, and finally Kosrae, with a surface area of 110 km2 (42.6 sq mi) and about 9,700 people.
The country’s official language is English. The official currency is the US Dollar.
I found an interesting article on founding Micronesia - Making Micronesia: A Political Biography of Tosiwo Nakayama