Loops in JavaScript

Learn how to repeat code efficiently using loops.

Why Use Loops?

Loops allow you to execute a block of code multiple times. Instead of writing repetitive code, you can use a loop to automate the process.

Pro Tip: Loops are essential for working with arrays and collections of data. Master them early!

The for Loop

The for loop is the most common loop. It has three parts: initialization, condition, and increment.

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Looping Through Arrays

One of the most common uses of loops is iterating through arrays.

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The while Loop

The while loop continues as long as a condition is true. Be careful to avoid infinite loops!

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Warning: Always ensure your while loop has a way to end. An infinite loop can crash your browser!

The do...while Loop

The do...while loop is similar to while, but it always executes at least once.

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The forEach Method

Arrays have a built-in forEach method that's a cleaner way to iterate.

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Break and Continue

Use break to exit a loop early and continue to skip to the next iteration.

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Challenge: FizzBuzz

Write a loop that prints numbers from 1 to 20. But for multiples of 3, print "Fizz" instead. For multiples of 5, print "Buzz". For multiples of both 3 and 5, print "FizzBuzz".

Your solution

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