How do I fix this error? and what does it mean?

arduino-builder/arduino-builder -compile -core-api-version 10611 -build-path /tmp/969053214 -hardware arduino-builder/hardware -hardware arduino-builder/packages/cores -tools arduino-builder/tools -tools arduino-builder/packages/tools -built-in-libraries arduino-builder/latest -libraries /tmp/907294971/pinned -libraries /tmp/907294971/custom -fqbn arduino:avr:uno -build-cache /tmp -verbose=false /tmp/907294971/sketch_may9a

/tmp/907294971/sketch_may9a/sketch_may9a.ino: In function 'void loop()':

/tmp/907294971/sketch_may9a/sketch_may9a.ino:43:12: error: 'class HardwareSerial' has no member named 'printIn'

/tmp/907294971/sketch_may9a/sketch_may9a.ino:46:12: error: 'class HardwareSerial' has no member named 'printIn'

exit status 1

Here is the coding below:

/* IR Breakbeam sensor demo! */

define LEDPIN 13

//Pin 13:Arduino has an LED connected on pin 13 //Pin 11:Teensy 2.0 has the LED on pin 11 //Pin 6:Teensy++ 2.0 has the LED on pin 6 //Pin 13:Teensy 3.0 has the LED on pin 13

define SENSORPIN 4

//variables will change: int sensorState = 0, lastState=0; //variable for reading the pushbutton status

void setup() { //initialize the LED pin as an output: pinMode(LEDPIN, OUTPUT); //initialize the sensor pin as an input: pinMode(SENSORPIN, INPUT); digitalWrite(SENSORPIN, HIGH);//turn on the pullup

Serial.begin(9600); }

void loop() { //read the state of the pushbutton value: sensorState = digitalRead(SENSORPIN);

//check if the sensor bea is broken //if it is, the sensorState is LOW: if (sensorState == LOW) { //turn LED on: digitalWrite(LEDPIN, HIGH); } else { //turn LED off: digitalWrite(LEDPIN, LOW); }

if (sensorState && !lastState) { Serial.printIn("Unbroken"); } if (!sensorState && lastState) { Serial.printIn("Broken"); } lastState = sensorState; }

println. That's a lower case L, not an uppercase I.