In a state of equilibrium all forces are in balance so there is no net force on an object. The object will be stationary, or in steady-state. However, not all equilibrium cases are alike. Different cases will, if disturbed, have different subsequent behaviors.

A stable equilibrium is one that restores itself to its original configuration after being disturbed. In this example, if you push the ball up the sides of the bowl, it will roll back down to where it was originally at rest.

A stable equilibrium is one that resists change.

Balancing the ball on the convex side of the bowl shows a case of unstable equilibrium. The ball starts out at rest---it's balanced at the top of the upside-down bowl---but if we disturb it, the ball rolls away and doesn't come back. Standing a stick on its end is another example of unstable equilibrium. As soon as you nudge the stick, it falls down.

Unstable equilibrium practically invites change to take place.

Neutral equilibrium is in-between stable and unstable. We nudge the ball away from its equilibrium position. It doesn't come back, so it's not stable; however, it doesn't roll away---it establishes a new equilibrium position wherever it's pushed---so it's not unstable.

Neutral conditions neither resist nor encourage changes.