The terms "Schwarzschild Radius" and "Event Horizon" are related but not interchangeable; the event horizon is the boundary beyond which nothing can escape a black hole, while the Schwarzschild radius defines the size of this boundary for a non-rotating black hole. The event horizon is a 2D surface that can be described in Schwarzschild coordinates, but these coordinates become singular at the horizon, complicating their interpretation. The Schwarzschild radius is specifically the radius from the singularity to the event horizon, but the singularity itself is not a physical point in space, as it represents a point in time after crossing the event horizon. Understanding these concepts is crucial for accurately discussing black hole physics, especially in educational contexts.