Yap (Waqab, sometimes written as Wa'ab) traditionally refers to an island group located in the Caroline Islands of the western Pacific Ocean, a part of Yap State. The name "Yap" in recent years has come to also refer to the state within the Federated States of Micronesia, inclusive of the Yap Main Islands and its various outer islands, the Yap Neighboring Islands. For specifying the island group, the name Yap Main Islands is most exact.
Yap is actually made up of four separate islands: Yap Proper (Marbaaq), Gagil-Tamil, Maap (Maap′), and Rumung. The four islands are encircled by a common coral reef and are separated by relatively small water features. Gagil-Tamil and Yap Proper were once linked, but in 1901 a narrow canal called the Tagireeng Canal was built to cut the two landmasses apart. Yap was formed from an uplift of the Philippine Sea Plate, and is referred to as a "high" island as opposed to atolls. The land is mostly rolling hills, with densely vegetated valleys and savanna interiors. Mangrove swamps line much of the shore, although there are beaches on the northern and western sides of the islands. Excluding the reef area, the Yap Main Islands are approximately 24 km long, 5–10 km wide, and 98 km^2. The highest elevation is at Mount Taabiywol in Fanif municipality on Yap Proper.
Administratively, the Yap Main Islands are divided into ten municipalities that sometimes cross the water features that divide Yap into its constituent islands.
Dalipebinaw
Fanif
Gagil
Gilman
Kanifay
Maap
Rull
Rumung
Tomil
Weloy
The climate type of Yap Island belongs to the typical tropical rainforest climate (Köppen: Af), with high temperature and rainy weather throughout the year, and the most humid time of the year is from June to October.
The Yapese people's indigenous cultures and traditions are strong compared to those of other states in Micronesia.
Yap is known for its stone money, known as Rai, or Fei: large doughnut-shaped, carved disks of (usually) calcite, up to 4 m (12 ft) in diameter (most are much smaller).