Lesson 3 - Control Flow

3.2 Loops

Loops are used to execute a block of code repeatedly. There are two types of loops available in JavaScript:

for loop: The for loop allows you to specify the number of times a code block executes. For example:

for (let i = 0; i < 5; i++) {
    console.log("The value of i is: " + i);
}

Here, the for loop will run until i < 5. Try to edit the condition.

while loop: The while loop runs a code block continuously until a pre-defined condition is met. Have a look at the following example:

let i = 0;
while (i < 5) {
    console.log("The value of i is: " + i);
    i++;
}

This loop will run until the value of i is less than 5. Here, i++ increases the value of i by one every time the loop runs.

Interrupting Loops: break: The keyword break is used to stop the execution of a loop when a certain condition is true.

for (let i = 0; i < 5; i++) {
    if (i == 3) break;
    console.log("The value of i is: " + i);
}

The above code will stop immediately when the value of i equals 3. Try to change the values and see what happens.

continue: The keyword continue is used to skip the execution of a specific code block when a certain condition is true.

for (let i = 0; i < 5; i++) {
    if (i == 3) continue;
    console.log("The value of i is: " + i);
}

Here, the program will skip printing when the value of i equals 3, which means it will print all the values except 3.