Now let's take a look at loops.

A loop is a structure that executes a set of instructions repeatedly while a certain condition is true.

There are three types of loops in JavaScript:

- **while**;
- **do-while**;
- **for**.

Let's take a closer look at each one.

# while
The `while` is the most simple loop. This operator repeats the code block while the condition is `true`.

To create this loop, you need to use the `while` keyword with **condition** in parentheses (`()`) and code block in curly brackets (`{}`). This syntax is similar to the `if` syntax:

```javascript
while (condition) {
  // code block
};
```

let a = 5;

while (a <= 10) {
  console.log("a =", a);
  a++;
};

The interpreter checks the condition and executes the code block if the condition is `true`. These actions repeat until the condition is `false`:

> Note
>
> Be careful with the condition! If the condition always evaluates to true, the loop will never break and will run indefinitely. Such moments are called infinity loops.

How many times will the program output "Hello!"?

How many times will the program output "JavaScript"?

How many times will the program output "Be careful!"

First, let's get acquainted with JavaScript and look at its syntax. In this section, you will get a basic familiarity with the JavaScript syntax to make it easier to learn in detail later on.

Now it's time to learn about the data types that JavaScript works with. We'll start by looking at the difference between literals and variables, and then delve into the various data types.

We have become familiar with the various data types. Now, let's learn how to work with them by learning the operations we can perform with each data type.

Next, we will learn how to control the flow of execution. It's a straightforward process: we can tell the interpreter exactly what to do under certain conditions.

Next, we will explore how to shorten code using repetitive looped actions. We will examine the types of loops available in JavaScript and learn how to work with them.

Finally, to be able to write simple programs, we need to learn about functions that can make our lives much easier. We will learn how to create and use our functions.