The imaginary line that divides the Earth into the Northern and Southern Hemispheres is called the Equator. It is positioned equidistant from the North and South Poles and has a latitude of 0 degrees. The Equator plays a significant role in geography and climate, as regions along this line typically experience a tropical climate with relatively consistent temperatures throughout the year. Additionally, the Equator affects the Earth's rotation, leading to phenomena like the Coriolis effect. It serves as a reference point for navigation and mapping, and it’s a key part of understanding the Earth's geographic and climatic systems.