Cut and fill
Cut and fill is like playing with a big pile of sand. Imagine you have a big pile of sand and you want to make a big hill. The higher the hill, the more sand you need.
Cutting is taking away some of the sand to make a hole. So, imagine you have a big pile of sand, and you dig a hole in it. Now you've cut the sand.
Filling is adding more sand to make it bigger. Let's say you have a hole in the sand, and you want to make it a hill. You need more sand to fill it up and make it higher.
Now imagine that big pile of sand again. You want to make a road on the sand, but the road is not flat, it has ups and downs. You need to cut some sand from the high parts and use that sand to fill the low parts, so the road is all smooth like. That's what cut and fill is all about - making the ground smooth before you can build on it.
Cutting is taking away some of the sand to make a hole. So, imagine you have a big pile of sand, and you dig a hole in it. Now you've cut the sand.
Filling is adding more sand to make it bigger. Let's say you have a hole in the sand, and you want to make it a hill. You need more sand to fill it up and make it higher.
Now imagine that big pile of sand again. You want to make a road on the sand, but the road is not flat, it has ups and downs. You need to cut some sand from the high parts and use that sand to fill the low parts, so the road is all smooth like. That's what cut and fill is all about - making the ground smooth before you can build on it.