Blinking LED with Arduino uno

1/*
2  Blinking LED project.
3  Turns on an LED on for one second,  then off for one second, repeatedly.
4  Last Modification modified 30 March 2020
5  by Roy Ben Avraham
6 */
7
8// the setup function runs once when you press  reset or power the board
9void setup() {
10  // initialize digital pin 13 as  an output.
11  pinMode(13, OUTPUT);
12}
13
14// the loop function runs over  and over again forever
15void loop() {
16  digitalWrite(13, HIGH);   // turn the  LED on (HIGH is the voltage level)
17  delay(1000);              // wait for a  second
18  digitalWrite(13, LOW);    // turn the LED off by making the voltage  LOW
19  delay(1000);              // wait for a second
20}
21