The traditional heat zone between the Tropic of Cancer and the Tropic of Capricorn is the Torrid Zone.
The Torrid Zone is the traditional geographical name for the belt surrounding the equator. In modern geographic usage, it is usually called the tropics or tropical zone. It extends from about 23.4° north latitude to about 23.4° south latitude, bounded by the two tropics.
Earth’s axial tilt explains the zone’s boundaries. Within this belt, the Sun can appear directly overhead at least once during the year. The overhead-Sun position shifts north and south between the Tropic of Cancer and Tropic of Capricorn as Earth orbits the Sun.
“Torrid” refers to heat, not to one uniform climate. Rainfall, elevation, ocean currents and seasonal wind systems create rainforests, savannas, deserts and highland climates inside the zone. The Torrid Zone is also different from the North and South Temperate Zones and the Frigid Zones, which are the other traditional heat zones.