Free course for beginners

JavaScript

Programming learning is an interesting and exciting process. The syntax of the language is the simplest and shortest path, without which it is impossible to start. This free online JavaScript course will introduce you to the basic concepts of the language. Learn the basics and write your first JS programs
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Where is the JavaScript programming language used?

JavaScript is a versatile and in-demand programming language that runs in all browsers and on the server side. With it, you can master web development, learn to create interactive websites, mobile applications, and server-side services. JavaScript is easy to learn, popular in the IT industry, and its large community and numerous job opportunities can help you quickly build a career

Learning preview
What will you learn in the "JavaScript" course?

You will learn the basic syntax of JavaScript — a fundamental skill that will help you understand other people's code and write your own programs. After the course, you’ll be able to create simple scripts, such as a calculator

Learning program

JavaScript is one of the most popular programming languages in the world. It is used to build interactive web pages, mobile applications, and in server-side development. You will learn JS from scratch, from the very beginning. The first module provides a launching pad for writing meaningful programs. We will find out how to write your first JS code. Learn what comments are and why programmers need them. By checking your solutions, we will examine what testing is and how to read the output of tests.

Modern applications are created to serve business goals, help in everyday life and entertain. However, they are still based on computations. The simplest and basic topic in programming is arithmetic. In this module, you will translate arithmetic operations into the programming language, talk about the operator precedence and operations with fractional numbers. We will recall math classes and find out what happens when you divide by zero in JavaScript. Finally, we will explain what a linter is and why it can be grumpy sometimes.

In programming, text is called string, and this topic is not that simple. How do you print a phrase that has both single and double quotation marks? How to deal with text at all, since the computer is unaware of any letters! This module deals with various aspects of text writing — from quotation marks and escaping to encoding.

Information can be stored in variables. They allow you to reuse already existing data and eliminate duplicates from your code. In this module, we will show you how to modify and name variables to make your code readable for any developer. You will find that naming a variable can be tricky! Learn how to use variables to simplify complex computations.

JavaScript is a weakly typed language with immutable primitive data types. What will happen if you try to multiply a number by a string? How does JavaScript recognize the type of a given data? And what does JavaScript do when it sees a type mismatch? Find the answers to these questions in the current module.

Concept of function defines any arbitrary operation in programming. Functions are the bricks from which programmers build systems. In this module, you will learn how to use built-in functions. We will examine the function signatures in the documentation and figure out how to use it. We get familiar with standard libraries which provide thousands of functions. You can’t memorize all the functions, so every programmer should know how to find documentation.

The data we use in our programs can have important properties. In JavaScript, properties are built-in directly into the language. Besides properties, there are methods — functions within properties. Properties and methods are expressions, just like variables, constants, or function calls, which means that you can combine them in many ways. We elaborate these topics deeply in separate courses dedicated to object-oriented features of JavaScript. Here we will cover the basics.

Defining your own functions makes writing and maintaining programs much easier. The ability to define functions, for example, allows complex (composite) operations to be merged into a single operation, with the complexity hidden behind a simple function. Learn to write functions and take the first step toward creating truly useful programs. This module will teach you how to name functions (as well as variables and constants) and create your own.

Logical expressions allow you to answer questions that arise during program operation. Is the user authenticated? Is the subscription paid? Is it a leap year? In this module, you will study predicate functions - those who ask a question and answer it - whether it is true or false. Practice writing such functions and move on to more complex logical expressions.

The task of the predicate function is to get an answer to the question, but you often need to go ahead and do something depending on the answer. If and Switch are JavaScript statements by which a programmer can determine the required program behavior depending on different conditions: skip certain instructions and run others. We will analyze them by practicing in this module.

Any code can be repeated thousands, millions, or even billions of times. This offers up a lot of possibilities for building programs and sophisticated systems when combined with the other tools you already know – variables and conditions. Here's an obvious example. In a 500-page book, you must locate a specific phrase. The phrase is fresh in your mind, but you can't recall the page number. The quickest (and most time-consuming) method is to go through each page until you find the right one. Loops are required for such repetitive activities.
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How the training is organised
Try it without registering
Start learning right away - first lessons are available without an account. If you like the format, you can register to save your progress
Convenient format
Everything you need to master new topics is on one screen. Theory, practice and live examples go hand in hand. The clear structure helps you to learn in a consistent manner and not to miss important details
Practice in the browser
You don't need to install anything - all tasks are performed right in your browser. Built-in code editor, console and automatic tests make learning comfortable. And if something fails, you can always see the teacher's solution
AI assistance without limits
AI explains topics, tells you how to solve assignments, and helps you at any time - like a personal tutor 24/7
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Sorting out the questions
How does the "JavaScript" course help in a programmer's career?

avaScript is a key tool for frontend developers. Knowledge of this language paves the way to a career in web development, allowing you to create dynamic websites, work with interfaces, and interact with users through the browser. Companies value specialists who know JavaScript because it is used on almost every modern website.

How is the "JavaScript" course structured?

You will learn through a beginner-friendly program that includes video lectures, theoretical materials, quizzes, and practical tasks. All exercises are automatically graded, and you will be able to write code directly in the browser. This format helps you quickly consolidate your knowledge and immediately apply it in practice.

Is a certificate provided at the end of the course?

No, a certificate is not issued upon completion of the course. However, you will gain all the necessary knowledge for a confident start in programming. You will learn to write code, work with logic, interact with web pages, and create small interactive elements for websites. These skills will serve as a solid foundation for further professional growth.

How quickly can you master JavaScript from scratch?

The speed of learning depends on your experience and the amount of time you are willing to dedicate to studying. The basics of syntax, variables, functions, and conditions can be understood within a few weeks of regular study.

What knowledge is needed before starting to study JavaScript?

It is helpful to have a basic understanding of HTML and CSS, as this will make it easier to understand how JavaScript interacts with the page structure. However, if you are a complete beginner, it won’t prevent you from starting the course. The course explains everything step by step and in simple language, with plenty of practice and examples.

Can you study JavaScript without knowing HTML and CSS?

Yes, you can start learning JavaScript without prior knowledge of HTML and CSS. However, since JavaScript is closely tied to how web pages work, it is recommended to study them simultaneously. This will help you see the results of your code and understand how different technologies interact in the browser.

Can JavaScript be used to create mobile applications?

Yes, JavaScript can be used not only for web development but also for creating mobile applications. With technologies like React Native, you can write cross-platform apps for iOS and Android using a single language. This makes JavaScript a versatile tool for both browsers and mobile platforms.