Final answer:
The zero datum for latitude is known as the equator, which is the reference line for measuring latitude north or south on Earth's surface.
Step-by-step explanation:
The zero datum for latitude is known as the equator. This imaginary line divides the Earth into the Northern and Southern Hemispheres and is the starting point for measuring latitude.
Latitude is a geographic coordinate that specifies the north-south position of a point on the Earth's surface, ranging from 0° at the equator to 90° North or South at the poles. Each location's latitude is measured in degrees north or south from the equator, and it's an essential part of the Earth's geographic coordinate system used for navigation and mapping.