Synthetic differential geometry

Synthetic differential geometry (SDG) is a way of studying shapes and motions without using traditional equations and calculations. Instead, it studies shapes and motions by using different kinds of words or symbols. It helps us to describe and analyze shapes and motions in a simple and efficient way. Think of it like a game where you describe shapes and motions with different words and symbols, but then you find out what those words and symbols really mean. The game helps us to understand shapes and motions without relying on equations.