Digital Temperature Module For Arduino

Routines source code:
int Led = 13 ;// define LED Interface
int buttonpin = 3; // define the digital temperature sensor interface
int val ;// define numeric variables val
void setup()
{
pinMode(Led, OUTPUT) ;// define LED as output interface
pinMode(buttonpin, INPUT) ;// define digital temperature sensor output interface
}
void loop ()
{
val = digitalRead(buttonpin) ;// digital interface will be assigned a value of 3 to read val
if(val == HIGH) // when the digital temperature sensor detects a signal, LED flashes
{
digitalWrite(Led, HIGH);
}
else
{
digitalWrite(Led, LOW);
}
}