Final answer:
Bistable systems are systems with two stable states. Examples include a light switch that can be in an on or off state until an external force changes its state.
Step-by-step explanation:
Bistable (biphasic) systems are systems with two stable states. These are systems that can exist in two distinct states, and once in a stable state, they tend to remain in that state until an external force is applied to change their state. A common example of a bistable system is a light switch, which can be in an on or off state.