Keyestudio KS0436 Kit Manual page 25

states tells the Arduino board that we are going to use the LED pin as
an output.
void loop()
It is also mandatory for a sketch to have a "loop" function. Unlike the
'setup' function that only runs once, after a reset, the 'loop' function
will, after it has finished running its commands, immediately start
again.
pinMode(ledPin, OUTPUT)
 Input Or Output ?:
Before you can use one of the digital pins, you need to tell the UNO
Board whether it is an INPUT or OUTPUT.
We use a built-in "function" called
digital output.
digitalWrite(ledPin, HIGH)
Digital Output :
digitalWrite(ledPin, LOW)
When you're using a pin as an OUTPUT, you can command it to be HIGH
(output 5 volts) or LOW (output 0 volts).
 What happens when you change the number in one or both of the
delay(1000)
pinMode() to make pin 10 a
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