Help me understand the continental divide?

Question

Help me understand the continental divide?

Answer 1

Its basically an imaginary line that says if water falls on this side it travels to this ocean or if it falls on this side it travels to the other ocean.

The line is basically a best guess on top of being imaginary.

Answer 2

The Continental Divide is the line at which water drains in different directions.  In North America, all water west or south of the Divide drains to the Pacific Ocean and all water east or north of the line drains either to the Atlantic or the Arctic ocean.