- JavaScript First Steps
- Looking to become a front-end web developer?
- Prerequisites
- Guides
- Assessments
- See also
- Found a content problem with this page?
- JavaScript Tutorial
- Examples in Each Chapter
- Example
- My First JavaScript
- Use the Menu
- Learn by Examples
- Why Study JavaScript?
- Learning Speed
- Commonly Asked Questions
- My Learning
- JavaScript References
- JavaScript Quiz Test
- JavaScript Exam — Get Your Diploma!
- Kickstart your career
- Современный учебник JavaScript
- Язык JavaScript
- Онлайн-курсы
- Основы веб-разработки
- JavaScript / DOM / Интерфейсы
- JavaScript / DOM / Интерфейсы
- Современная верстка
- Архитектура и паттерны
- Фреймворки, смежные технологии
- Angular
- Node.js
- React
- TypeScript
- Vue.js
- RxJs
- Браузер: документ, события, интерфейсы
- Тематические разделы
- Следите за обновлениями javascript.ru
- Комментарии
JavaScript First Steps
In our first JavaScript module, we first answer some fundamental questions such as «what is JavaScript?», «what does it look like?», and «what can it do?», before moving on to taking you through your first practical experience of writing JavaScript. After that, we discuss some key building blocks in detail, such as variables, strings, numbers and arrays.
Looking to become a front-end web developer?
We have put together a course that includes all the essential information you need to work towards your goal.
Prerequisites
Before starting this module, you don’t need any previous JavaScript knowledge, but you should have some familiarity with HTML and CSS. You are advised to work through the following modules before starting on JavaScript:
Note: If you are working on a computer/tablet/other device where you don’t have the ability to create your own files, you could try out (most of) the code examples in an online coding program such as JSBin or Glitch.
Guides
Welcome to the MDN beginner’s JavaScript course! In this first article we will look at JavaScript from a high level, answering questions such as «what is it?», and «what is it doing?», and making sure you are comfortable with JavaScript’s purpose.
Now you’ve learned something about the theory of JavaScript, and what you can do with it, we are going to give you a crash course on the basic features of JavaScript via a completely practical tutorial. Here you’ll build up a simple «Guess the number» game, step by step.
When you built up the «Guess the number» game in the previous article, you may have found that it didn’t work. Never fear — this article aims to save you from tearing your hair out over such problems by providing you with some simple tips on how to find and fix errors in JavaScript programs.
After reading the last couple of articles you should now know what JavaScript is, what it can do for you, how you use it alongside other web technologies, and what its main features look like from a high level. In this article, we will get down to the real basics, looking at how to work with the most basic building blocks of JavaScript — Variables.
At this point in the course, we discuss maths in JavaScript — how we can combine operators and other features to successfully manipulate numbers to do our bidding.
Next, we’ll turn our attention to strings — this is what pieces of text are called in programming. In this article, we’ll look at all the common things that you really ought to know about strings when learning JavaScript, such as creating strings, escaping quotes in strings, and joining them together.
Now we’ve looked at the very basics of strings, let’s move up a gear and start thinking about what useful operations we can do on strings with built-in methods, such as finding the length of a text string, joining and splitting strings, substituting one character in a string for another, and more.
In the final article of this module, we’ll look at arrays — a neat way of storing a list of data items under a single variable name. Here we look at why this is useful, then explore how to create an array, retrieve, add, and remove items stored in an array, and more besides.
Assessments
The following assessment will test your understanding of the JavaScript basics covered in the guides above.
In this assessment, you’ll be tasked with taking some of the knowledge you’ve picked up in this module’s articles and applying it to creating a fun app that generates random silly stories. Have fun!
See also
An excellent resource for aspiring web developers — Learn JavaScript in an interactive environment, with short lessons and interactive tests, guided by automated assessment. The first 40 lessons are free, and the complete course is available for a small one-time payment.
Found a content problem with this page?
This page was last modified on Jul 3, 2023 by MDN contributors.
Your blueprint for a better internet.
JavaScript Tutorial
JavaScript is the world’s most popular programming language.
JavaScript is the programming language of the Web.
JavaScript is easy to learn.
This tutorial will teach you JavaScript from basic to advanced.
Examples in Each Chapter
With our «Try it Yourself» editor, you can edit the source code and view the result.
Example
My First JavaScript
Use the Menu
We recommend reading this tutorial, in the sequence listed in the menu.
If you have a large screen, the menu will always be present on the left.
If you have a small screen, open the menu by clicking the top menu sign ☰ .
Learn by Examples
Examples are better than 1000 words. Examples are often easier to understand than text explanations.
This tutorial supplements all explanations with clarifying «Try it Yourself» examples.
If you try all the examples, you will learn a lot about JavaScript, in a very short time!
Why Study JavaScript?
JavaScript is one of the 3 languages all web developers must learn:
1. HTML to define the content of web pages
2. CSS to specify the layout of web pages
3. JavaScript to program the behavior of web pages
This tutorial covers every version of JavaScript:
- The Original JavaScript ES1 ES2 ES3 (1997-1999)
- The First Main Revision ES5 (2009)
- The Second Revision ES6 (2015)
- All Yearly Additions (2016, 2017, 2018, 2019, 2020)
Learning Speed
In this tutorial, the learning speed is your choice.
If you are struggling, take a break, or re-read the material.
Always make sure you understand all the «Try-it-Yourself» examples.
The only way to become a clever programmer is to: Practice. Practice. Practice. Code. Code. Code !
Commonly Asked Questions
You don’t have to get or download JavaScript.
JavaScript is already running in your browser on your computer, on your tablet, and on your smart-phone.
JavaScript is free to use for everyone.
My Learning
Track your progress with the free «My Learning» program here at W3Schools.
Log in to your account, and start earning points!
This is an optional feature. You can study W3Schools without using My Learning.
JavaScript References
W3Schools maintains a complete JavaScript reference, including all HTML and browser objects.
The reference contains examples for all properties, methods and events, and is continuously updated according to the latest web standards.
JavaScript Quiz Test
Test your JavaScript skills at W3Schools!
JavaScript Exam — Get Your Diploma!
Kickstart your career
Get certified by completing the course
Современный учебник JavaScript
Перед вами учебник по JavaScript, начиная с основ, включающий в себя много тонкостей и фишек JavaScript/DOM.
Первые две части посвящены JavaScript и его использованию в браузере. Затем идут дополнительные циклы статей на разные темы.
Язык JavaScript
Здесь вы можете изучить JavaScript, начиная с нуля и заканчивая продвинутыми концепциями вроде ООП.
Мы сосредоточимся на самом языке, изредка добавляя заметки о средах его исполнения.
Онлайн-курсы
Онлайн-курсы — это не быстро устаревающие видео-записи, а живые вебинары. Ведёт их преподаватель — опытный действующий разработчик. С теорией, практикой, ответами на вопросы, проектом и обратной связью по вашему коду («code review»).
Основы веб-разработки
JavaScript / DOM / Интерфейсы
JavaScript / DOM / Интерфейсы
Современная верстка
Архитектура и паттерны
Фреймворки, смежные технологии
Angular
Node.js
React
TypeScript
Vue.js
RxJs
Браузер: документ, события, интерфейсы
Изучаем работу со страницей – как получать элементы, манипулировать их размерами, динамически создавать интерфейсы и взаимодействовать с посетителем.
Тематические разделы
Следите за обновлениями javascript.ru
Комментарии
- Если вам кажется, что в статье что-то не так — вместо комментария напишите на GitHub.
- Для одной строки кода используйте тег , для нескольких строк кода — тег , если больше 10 строк — ссылку на песочницу (plnkr, JSBin, codepen…)
- Если что-то непонятно в статье — пишите, что именно и с какого места.