Lyapunov stability

Lyapunov stability is a way of looking at the behavior of a system over time. It is named after the Russian mathematician Aleksandr Lyapunov. It tells us if a system can stay in the same state or if its behavior will become more and more unpredictable as time goes on. Imagine a boat floating on a lake. We can use Lyapunov stability to find out if the boat will stay in the same place or if it will drift away. If a system is Lyapunov stable, then it will stay in the same state and if it is not stable, then its behavior will become more and more unpredictable.