The lines that run horizontally circling the globe are called latitude lines.

Here's a breakdown:

* Latitude measures distance north or south of the equator.

* Latitude lines are imaginary circles that run parallel to the equator.

* The equator is the largest latitude line, dividing the Earth into the Northern and Southern Hemispheres.

* Other latitude lines are measured in degrees, with the North Pole being 90 degrees North and the South Pole being 90 degrees South.

Let me know if you have any other questions about latitude lines or geography!