Sensor Light Controls

Most houses have some sort of front door or yard light.  Some of these lights are controlled by a sensor.  If the light is switched on .. it only turns on of the sun has set and the yard is dark.

On Mr. Widmer's wall is a typical setup.  It has an input and an output part to the system.  It is a simple Boolean system. The light only goes "ON" if the light sensor is "dark" AND the movement sensor is set "TRUE" -- something moves in front of the sensor.
These are the typical symbols used on  Boolean logic circuit.  They are read from left to right. An "AND" circuit will only show 5 V if both inputs ( left ) show 5 V The "NOT" circuit flips the 5V to 0V The "OR" circuit will only show 5V ( or TRUE ) if  either of the left-hand circuits transmit 5V