Okay kiddo, so you know how sometimes people have to use math to aim or shoot things, right? Well, rangekeeping is a type of math that helps people figure out how far they are from the thing they're trying to hit.
Here's how it works: imagine you're playing ball with your friends and someone throws the ball really far away. You have to figure out how hard to throw the ball back to hit your friend. Rangekeeping helps you do that by giving you a number that tells you how far away your friend is, so you can figure out how hard to throw the ball.
Now, things can get a bit tricky when you're trying to aim bigger things, like ships or airplanes. Rangekeeping helps with this too, by using special math formulas to calculate the distance between your ship and the enemy ship or airplane. This helps you aim your weapons more accurately and hit the target.
So rangekeeping is all about using math to figure out distances and make accurate shots, whether you're playing ball with your friends or fighting a big battle at sea. Pretty cool, right?