States

A light switch can be “on” or “off”. “on” and “off” are called “states”. The light switch has two states.

A toilet has three states:

1. 2 seats up
2. 1 seat up
3. 2 seats down

Can you think of anything else that has states?

Traffic lights can be red, yellow, or green.

Pantograph can be up on the Wire or down on the bus

Tires can turn left or right

A 20 sided die, which looks like this, has 20 states

As you think about more things at the same time, the number of states goes up. For instance, if you think about two switches, there are 4 states:

1. A and B both on
2. A on, B off
3. A off, B on
4. A and B both off

Three switches have 8 states:

How many states do 4 switches have?

State space

If you pretend that there is a box in your room for each state, this is called a state space. Imagine a ball that moves to the correct box each time your toilet seat moves. When both seats are up, the ball in one box.

As soon as one seat is put down, the ball moves to another box.