A state machine in programming is a way to model how a system behaves depending on its current state and inputs/events.

Core Idea#

A system can be in one state at a time (like “idle”, “running”, “paused”).

When an event/input happens, the system can transition to another state.

The rules for moving between states are called transitions.

Example (Simple Traffic Light)#

States:

• Red
• Green
• Yellow

Transitions:

• From Red → Green
• From Green → Yellow
• From Yellow → Red

Why Use a State Machine?#

• Clarity: Helps organize complex logic in a clean way.

• Predictability: You always know what states are possible and how transitions happen.

Summary#

A state machine is essentially a description of:

• The states something can be in (e.g., Playing, Paused, or Stopped for a music player).
• The events or inputs it can receive (e.g., play button pressed, pause button pressed, stop button pressed).
• The transitions — what happens when an event occurs in a given state (e.g., Paused + play → Playing).
• The actions (optional) — what to do when entering, exiting, or during a state.

So yes — it’s like a map of how a system behaves, showing all possible states and how the system moves between them.