Summary  
This chapter introduces the do-while loop, a control structure that executes a code block once before evaluating its boolean condition and then repeats the block as long as the condition remains true.

General domain of usage  
printing a sequence of numbers

The `do-while` is very similar to a `while` loop, except it is always **executed at least once**, even if the **loop condition** is `false`. 

Another difference is that the code block is executed **before** the loop condition is checked. 


The general syntax of a `do-while` loop is the following:

```js
do {
  // code to execute
} while(boolean_expression);
```

The flowchart describes the execution process of a `do-while` loop:

For example, following is a program which uses a `do-while` loop to print the first ten even numbers:

let i = 1;

do { 
  console.log(i * 2);
  i += 1;
} while (i <= 10);

Even if we change the value of `i`, such that the condition becomes `false`, the code block will still execute at least once:

let i = 11;

do { 
  console.log(i * 2);
  i += 1;
} while (i <= 10);

What is the key difference between a `while` loop and a `do-while` loop?

What will be the output of the following code?

Dive into the world of the most popular language for front-end development – JavaScript. JavaScript is a language built into almost every browser and can be used for a wide variety of tasks. Learn the basic functionality and prepare yourself for the challenges and more advanced programming techniques.

An introduction to JavaScript, covering the basic syntax of the language along with key terms and concepts that form the foundation for learning advanced features. The section includes hands-on tasks designed to help practice these concepts and make the content easy to remember without effort.

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The `do-while` Loop

1. What is the key difference between a `while` loop and a `do-while` loop?

2. What will be the output of the following code?

Awesome!

The `do-while` Loop

1. What is the key difference between a `while` loop and a `do-while` loop?

2. What will be the output of the following code?

The `do-while` Loop

1. What is the key difference between a while loop and a do-while loop?

2. What will be the output of the following code?

Awesome!

The `do-while` Loop

1. What is the key difference between a while loop and a do-while loop?

2. What will be the output of the following code?

1. What is the key difference between a `while` loop and a `do-while` loop?

1. What is the key difference between a `while` loop and a `do-while` loop?