Gradian
A gradian is like a way of measuring angles, kind of like using a ruler to measure how long something is. But instead of measuring how long something is, we are measuring how far apart two things are when looked at from a certain point.
Imagine standing in the middle of a big circle, and looking out towards the edge. If you wanted to measure how far apart two things on the edge of the circle are, you would use something like degrees or radians. But if you wanted to use gradian instead, it's like dividing the circle into 400 pieces that are all the same size (something called a "right angle"). So, if you wanted to measure an angle that was half of the circle, you would use 200 gradian instead of 180 degrees or pi radians.
It's not so different from using degrees or radians to measure angles, but sometimes it's easier to use gradian because it's based on a division of the circle into 400 pieces, which can make calculations easier for some people.
Imagine standing in the middle of a big circle, and looking out towards the edge. If you wanted to measure how far apart two things on the edge of the circle are, you would use something like degrees or radians. But if you wanted to use gradian instead, it's like dividing the circle into 400 pieces that are all the same size (something called a "right angle"). So, if you wanted to measure an angle that was half of the circle, you would use 200 gradian instead of 180 degrees or pi radians.
It's not so different from using degrees or radians to measure angles, but sometimes it's easier to use gradian because it's based on a division of the circle into 400 pieces, which can make calculations easier for some people.
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