Summary  
This chapter introduces conditional statements—specifically the `if` statement—to evaluate Boolean expressions and execute code blocks only when specified conditions are met.

General domain of usage  
User access control (e.g., checking login status or age-based permissions)

A **conditional statement**, also known as an **if-statement**, can be used to execute specific lines of code based on the result of a **boolean expression**.

Definition

The **syntax** of a **conditional statement** is:
```js
if (boolean_expression)
{
   // some code here …
}
```

Here `boolean_expression` can be any expression which defines a **condition**. The code between the curly brackets (`{}`) is executed if the `boolean_expression` evaluates to `true`.

The code enclosed between the curly brackets (`{}`) is collectively referred to as a **Code Block**.

Note

let age = 18;

if(age >= 18) {
  console.log("The user is old enough to drive.");
}

We can have multiple **if-statements** in a program, giving us more control over which code block to execute. For example, we can further extend the previous code to output a different statement if the age is less than 18:


let age = 17;

if(age >= 18) {
    console.log("The user is old enough to drive.");
}

if(age < 18) {
    console.log("The user is not old enough to drive");
}

What is a conditional statement used for in JavaScript?

What is the correct syntax for an `if` statement?

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.

The `if` Statement

1. What is a conditional statement used for in JavaScript?

2. What is the correct syntax for an `if` statement?

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

The `if` Statement

1. What is a conditional statement used for in JavaScript?

2. What is the correct syntax for an if statement?

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

2. What is the correct syntax for an `if` statement?