Imagine you have a big puzzle that you want to solve. You start by shuffling the pieces around, but you need to make sure that your movements won't mess up the work you have already done.
A symplectic matrix is like a set of rules that you need to follow while you are moving the pieces around. It ensures that no matter how many times you move the pieces, the final puzzle will still look the same as it did at the beginning.
In math terms, a symplectic matrix is a special kind of matrix that preserves a geometric structure called the symplectic form. This symplectic form is like a set of rules that ensure that specific properties of an object in space will not change as it moves around.
So, a symplectic matrix is like a set of rules that help you move things around in space without changing important properties of that object. It's like a puzzle solver's cheat sheet, and it helps mathematicians solve complex problems without getting stuck.