Lesson: JavaScript Loops and Conditions

What are Loops in JavaScript?

A loop is used to repeat a block of code multiple times. JavaScript provides several types of loops: `for`, `while`, and `do...while`. Loops help automate repetitive tasks in programming.

Types of Loops

• For Loop: Used when you know how many times you want to run a statement or a block of statements.
• While Loop: Used when you want to run a block of code as long as the specified condition is true.
• Do...While Loop: Similar to the `while` loop, but it always runs at least once, even if the condition is false.

What are Conditions in JavaScript?

Conditions are used to perform different actions based on different scenarios. JavaScript uses the `if` statement to check a condition and run the appropriate block of code based on whether the condition is true or false.

Example of a `for` Loop

This is an example of a `for` loop that runs 5 times and logs the current iteration to the console:

            
for (let i = 1; i <= 5; i++) {
    console.log('Iteration ' + i);
}
            
        

Example of a `while` Loop

This is an example of a `while` loop that continues to run as long as a variable is less than 5:

            
let i = 1;
while (i <= 5) {
    console.log('Iteration ' + i);
    i++;
}
            
        

Example of an `if` Condition

This is an example of an `if` condition checking if a number is positive or negative:

            
let num = -5;
if (num > 0) {
    console.log('The number is positive');
} else {
    console.log('The number is negative');
}
            
        

Interactive Example

Click the button below to see how loops and conditions work:

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