// 2009 mlab.uiah.fi/paja
// Basic structure

// setup() and loop() are mandatory functions. Setup() only runs once after pressing a reset 
// button or power is supplied. loop() is excuted consecutively after setup ran.
// As both functions don't return any value, datatype is set as void.

void setup() // The setup function will only run once, after each powerup or reset of the Arduino board.
{ // functions always have to start with a curly brace and end with a closing curly brace.
  
  // Each statement always have to end with ";" (semicolon) symbol. Otherwise compiler will return a error.
  Serial.begin(9600);
}

void loop() // as the name suggests, the loop function runs consecutively. 
{
  // Select "Serial monitor" button after uploading this code.
  Serial.println("Hello world");
}