The required library depends on the micro module used.

int Led = 13 ;

int buttonpin = 7;

int val = 0;

void setup () {

pinMode (Led, OUTPUT) ;

pinMode (buttonpin, INPUT) ;

}

void loop () {

val = digitalRead(buttonpin);

if (val == HIGH) {

digitalWrite (Led, HIGH);

} else {

digitalWrite (Led, LOW);

}

}