Micronesia is a subregion of Oceania, composed of thousands of small islands in the western Pacific Ocean. It has a shared cultural history with 2 other island regions, Polynesia to the east and Melanesia to the south. The region has a tropical marine climate, and is part of the Oceania ecozone. There are 4 main archipelagos along with numerous outlying islands.
Micronesia is divided politically among several sovereign countries. One of these is the Federated States of Micronesia, which is often called "Micronesia" for short and is not to be confused with the overall region. The Micronesia region encompasses 5 sovereign, independent nations - the Federated States of Micronesia, Palau, Kiribati, Marshall Islands, and Nauru - as well as 3 U.S. territories in the northern part: Northern Mariana Islands, Guam, and Wake Island.
Description by Wikipedia