Insulindia is used as a geopolitical term in academic discussions of the former European colonial possessions within the Maritime Southeast Asia, especially the Dutch East Indies and Portuguese East Indies ("Portuguese Insulindia") much as former French colonial possessions in Southeast Asia are still termed French Indochina. It is also used to describe and locate the Chinese cultural diaspora (the "insulindian Chinese") across the islands of Southeast Asia.
The tropics is a region of the Earth surrounding the Equator. It is limited in latitude by the Tropic of Cancer in the northern hemisphere at approximately 23° 26′ 16″ (or 23.4378°) N and the Tropic of Capricorn in the southern hemisphere at 23° 26′ 16″ (or 23.4378°) S; these latitudes correspond to the axial tilt of the Earth. The tropics are also referred to as the tropical zone and the torrid zone (see geographical zone). The tropics include all the areas on the Earth where the Sun reaches a point directly overhead at least once during the solar year.
The tropics are distinguished from the other climatic and biomatic regions of Earth, the middle latitudes and the polar regions on either side of the equatorial zone.