[xhkkffbf]

Why not just squares or rectangles? Is there a simple explanation?

[meowtimemania]

Because it’s hard to cover a sphere in rectangles and have no rectangle overlap.

It’s the same reason soccer balls aren’t covered in squares/rectangles but rather hexagons.

[jt_b]

You want a shape that can represent an approximately equal area, anywhere on a 3 dimensional surface.