A loop allows a program to execute the same instructions repeatedly. Loops are important in Arduino because many applications require continuous monitoring of sensors and devices.

3.5.1 for Loop

A for loop is commonly used when the number of repetitions is known.

for (int i = 0; i < 5; i++) {

  Serial.println(i);

}

This program prints numbers from 0 to 4.

The three parts are:

for (initialization; condition; increment)

3.5.2 while Loop

A while loop continues executing as long as its condition remains true.

int counter = 0;

while (counter < 5) {

  Serial.println(counter);

  counter++;

}

3.5.3 do…while Loop

A do…while loop executes its instructions at least once, then checks the condition.

int counter = 0;

do {

  Serial.println(counter);

  counter++;

} while (counter < 5);

Importance of Loops in Arduino

Loops can be used to:

• Read sensors repeatedly.
• Blink LEDs.
• Count events.
• Control motors.
• Monitor switches.
• Update displays.
• Process incoming data.