JavaScript Tutorial for Beginners

JavaScript is the most popular programming language for web development. It allows you to create websites, applications, and interactive games. This course, aimed at beginners, will show you the basics of JavaScript. Let's get started!

What is JavaScript?

JavaScript is a scripting language used to control web behavior. It works with HTML and CSS. HTML defines the content, CSS defines the style, and JavaScript defines it dynamically.

Example:

Clicking a button changes something on the page; JavaScript does the same.

Why  learn JavaScript?

• Multi-purpose: All modern websites use JavaScript.

• Career: Many high-paying developer jobs require knowledge of JavaScript.

• Full stack build: JavaScript running on both front and back end.

• Interactive websites: You can create pop-ups, sliders, forms and animations.

• Easy to learn: JavaScript has a predictable syntax.

Required tools:

You don't need special tools to get started with JavaScript. Here's what you'll need:

• Web browser (such as Chrome or Firefox).

• Text editor (similar to VS Code or Notepad++)

• Optional: Online JS game (such as JSFiddle or CodePen)

How to write JavaScript:

JavaScript can be written in two ways:

1. Inline HTML

<button onclick="alert('Hello!')">Click here</button>

2. External file

<script src="script.js"></script>

Insert the script.js file as follows:

alert("Welcome to JavaScript!");

Basic JavaScript Syntax

1. Variables

Variables store data. Use allow, const, or var.

let name = "John";

const age = 25;

• let: Mutable variable that uses

• const: Used for values ​​that remain unchanged

• var: Previous path, now deprecated

2. Data Types

Common data types are:

• String: Text, such as "Hello"

• Number: Example, 100, 3.14

• Boolean: True or False

• Array: A list of elements, such as [1, 2, 3]

• Object: Key-value pairs

Example:

 let User = {

    Name: "Alice",

    Age: 30

};

3. Functions

Functions perform a task or response value.

function Greet() {

     alert("Hello!");

}

greet();

4. Events

JavaScript responds to user actions via events.

Example:

<button onclick="SayHello()">say Hello</button>

<script>

function sayHello() {

   alert("Hello user!");

}

</script>

5. Conditional statements

They are used to make decisions in the code.

 let age = 18 ;

if (age >= 18) {

    alert("You are of legal age.");

} else {

     alert("You are of legal age.");

} 

6. Leaves

They are used to repeat the process.

for (let i = 0; i < 5; i++) {

     console.log("Number: " + i);

} 

7. Arrays and objects

The array is as follows:

let fruits = ["apple", "banana", "orange"];

console.log(fruits[1]); // Source: banana

Object:

let car  = { 

    brand: "Toyota", p

    color: "red"

};

console.log(car.brand); // Source: Toyota

JavaScript in the browser

JavaScript works with the DOM (Document Object Model) directly in the browser.

Access and edit HTML elements.

Example:

<p id="demo">This is a section.</p>

<button onclick="changeText()">Change text</button>

<script> 

function changeText() { .

   document.getElementById("demo").innerHTML = "Document changed!";

} 

</script> 

Basic JavaScript Projects

Here are some projects that are good for beginners:

• Math: Perform basic calculations.

• To-do list: Add and delete tasks.

• Form validation: Check if fields are filled in correctly.

• Digital clock: Display the time to the second.

• Testing app: Create a simple testing game.

These projects will quickly improve your skills.

JavaScript best practices

• Always end a sentence with a semicolon (;)

• Use meaningful variable names.

• Keep your code clean and comment.

• Remove global variables

• Try writing code every day

JavaScript errors

• Missing half a period.

• Incorrect variable names

• Correct syntax

• Defined values

• This is an emotional situation.

Check your browser console for any error messages.

Learn JavaScript fast.

• Learn every day on Code Pen, Free Code Campus or W3 Schools platforms

• Watch the tutorial on YouTube

• Follow the blogs and join the community

• Create small projects regularly

JavaScript Workflow

• Once you are familiar with JavaScript, you will discover

• Frame: Responsive, Angle, Vue

• Context: node.js, express.js

• Full storage development

• Mobile application development: a localized answer

• Game development: Phaser.js

Conclusion

JavaScript is a must-have programming language for web developers. It is simple, powerful and widely used. Start with the basics, try small projects and move on to more advanced lessons. We learn every day and soon you will be doing something amazing on the web.