Lyapunov's Direct Method is a technique used in control theory and stability analysis to determine the stability of dynamical systems. It involves constructing a Lyapunov function, which is a scalar function that helps assess whether the system's state will converge to an equilibrium point over time. If the function decreases along the trajectories of the system, it indicates stability. The method is particularly useful because it does not require solving the system's differential equations. Instead, it focuses on the properties of the Lyapunov function to infer stability, making it applicable to a wide range of systems, including nonlinear ones.