For this lab, we learned how to use an analog input with the Arduino to go precise, granular readings on inputs rather than the simple 0 or 1 of digital.  We start by building a circuit with variable analog resistors.  I used a pair of force-sensing resistors, which read how much pressure is being applied to them.  Here’s the assembled board:

Once the circuit was assembled and powered, I could apply pressure to one of the sensors and the red LED would light up according to how hard I pressed.  Very cool:

I went through some of the sketches in the lab, one of which allowed me to print a numerical reading of my analog sensor to the console, like so:

The numbers are totally granular, and respond smoothly to how hard I squeeze the sensor.  This could have endless applications, as this number could be translated to control absolutely anything based on any analog sensor reading.

Yea for analog input.