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  2. Learn web development
  3. JavaScript

JavaScript

JavaScript is a programming language that allows you to implement complex things on web pages — every time a web page does more than just sit there and display static information for you to look at — displaying timely content updates, or interactive maps, or animated 2D/3D graphics, or scrolling video jukeboxes, etc. — you can bet that JavaScript is probably involved.

Learning pathway

JavaScript is arguably more difficult to learn than related technologies such as HTML and CSS. Before attempting to learn JavaScript, you are strongly advised to get familiar with at least these two technologies first, and perhaps others as well. Start by working through the following modules:

  • Getting started with the Web
  • Introduction to HTML
  • Introduction to CSS

Having previous experience with other programming languages might also help.

After getting familiar with the basics of JavaScript, you should be in a position to learn about more advanced topics, for example:

  • JavaScript in depth, as taught in our JavaScript guide
  • HTML5 APIs

Modules

This topic contains the following modules, in a suggested order for working through them.

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 JavaScript features in detail, such as variables, strings, numbers and arrays.
JavaScript building blocks
In this module, we continue our coverage of all JavaScript's key fundamental features, turning our attention to commonly-encountered types of code block such as conditional statements, loops, functions, and events. You've seen this stuff already in the course, but only in passing — here we'll discuss it all explicitly.
Introducing JavaScript objects
In JavaScript, most things are objects, from core JavaScript features like strings and arrays to the browser APIs built on top of JavaScript. You can even create your own objects to encapsulate related functions and variables into efficient packages. The object-oriented nature of JavaScript is important to understand if you want to go further with your knowledge of the language and write more efficient code, therefore we've provided this module to help you. Here we teach object theory and syntax in detail, look at how to create your own objects, and explain what JSON data is and how to work with it.
Client-side web APIs
When writing client-side JavaScript for web sites or applications, you won't go very far before you start to use APIs — interfaces for manipulating different aspects of the browser and operating system the site is running on, or even data from other web sites or services. In this module we will explore what APIs are, and how to use some of the most common APIs you'll come across often in your development work. 

Solving common JavaScript problems

Use JavaScript to solve common problems provides links to sections of content explaining how to use JavaScript to solve very common problems when creating a webpage.

See also

JavaScript on MDN
The main entry point for core JavaScript documentation on MDN — this is where you'll find extensive reference docs on all aspects of the JavaScript language, and some advanced tutorials aimed at experienced JavaScripters.
Coding math
An excellent series of video tutorials to teach the math you need to understand to be an effective programmer, by Keith Peters.

Document Tags and Contributors

Tags: 
  • Beginner
  • CodingScripting
  • JavaScript
  • JavaScripting beginner
  • l10n:priority
  • Landing
  • Module
  • Topic
 Contributors to this page: SphinxKnight, mrmsoares, rain1992, chrisdavidmills, rmateus, OrthoLearner, Jeremie, Sebastianz, bbstudio03, atymchuk, Andrew_Pfeiffer, fscholz
 Last updated by: SphinxKnight, Jul 18, 2017, 11:35:11 PM
See also
  1. Complete beginners start here!
  2. Getting started with the Web
    1. Getting started with the Web overview
    2. Installing basic software
    3. What will your website look like?
    4. Dealing with files
    5. HTML basics
    6. CSS basics
    7. JavaScript basics
    8. Publishing your website
    9. How the Web works
  3. HTML — Structuring the Web
  4. Introduction to HTML
    1. Introduction to HTML overview
    2. Getting started with HTML
    3. What's in the head? Metadata in HTML
    4. HTML text fundamentals
    5. Creating hyperlinks
    6. Advanced text formatting
    7. Document and website structure
    8. Debugging HTML
    9. Assessment: Marking up a letter
    10. Assessment: Structuring a page of content
  5. Multimedia and embedding
    1. Multimedia and embedding overview
    2. Images in HTML
    3. Video and audio content
    4. From object to iframe — other embedding technologies
    5. Adding vector graphics to the Web
    6. Responsive images
    7. Assessment: Mozilla splash page
  6. HTML tables
    1. HTML tables overview
    2. HTML table basics
    3. HTML Table advanced features and accessibility
    4. Assessment: Structuring planet data
  7. CSS — Styling the Web
  8. Introduction to CSS
    1. Introduction to CSS overview
    2. How CSS works
    3. CSS syntax
    4. Selectors introduction
    5. Simple selectors
    6. Attribute selectors
    7. Pseudo-classes and pseudo-elements
    8. Combinators and multiple selectors
    9. CSS values and units
    10. Cascade and inheritance
    11. The box model
    12. Debugging CSS
    13. Assessment: Fundamental CSS comprehension
  9. Styling text
    1. Styling text overview
    2. Fundamental text and font styling
    3. Styling lists
    4. Styling links
    5. Web fonts
    6. Assessment: Typesetting a community school homepage
  10. Styling boxes
    1. Styling boxes overview
    2. Box model recap
    3. Backgrounds
    4. Borders
    5. Styling tables
    6. Advanced box effects
    7. Assessment: Creating fancy letterheaded paper
    8. Assessment: A cool-looking box
  11. CSS layout
    1. CSS layout overview
    2. Introduction
    3. Floats
    4. Positioning
    5. Practical positioning examples
    6. Flexbox
    7. Grids
  12. JavaScript — Dynamic client-side scripting
  13. JavaScript first steps
    1. JavaScript first steps overview
    2. What is JavaScript?
    3. A first splash into JavaScript
    4. What went wrong? Troubleshooting JavaScript
    5. Storing the information you need — Variables
    6. Basic in JavaScript — Numbers and operators
    7. Handling text — Strings in JavaScript
    8. Useful string methods
    9. Arrays
    10. Assessment: Silly story generator
  14. JavaScript building blocks
    1. JavaScript building blocks overview
    2. Making decisions in your code — Conditionals
    3. Looping code
    4. Functions — Reusable blocks of code
    5. Build your own function
    6. Function return values
    7. Introduction to events
    8. Assessment: Image gallery
  15. Introducing JavaScript objects
    1. Introducing JavaScript objects overview
    2. Object basics
    3. Object-oriented JavaScript for beginners
    4. Object prototypes
    5. Inheritance in JavaScript
    6. Working with JSON data
    7. Object building practise
    8. Assessment: Adding features to our bouncing balls demo
  16. Accessibility — Make the web usable by everyone
  17. Accessibility guides
    1. Accessibility overview
    2. What is accessibility?
    3. HTML: A good basis for accessibility
    4. CSS and JavaScript accessibility best practices
    5. WAI-ARIA basics
    6. Accessible multimedia
    7. Mobile accessibility
  18. Accessibility assessment
    1. Assessment: Accessibility troubleshooting
  19. Tools and testing
  20. Cross browser testing
    1. Cross browser testing overview
    2. Introduction to cross browser testing
    3. Strategies for carrying out testing
    4. Handling common HTML and CSS problems
    5. Handling common JavaScript problems
    6. Handling common accessibility problems
    7. Implementing feature detection
    8. Introduction to automated testing
    9. Setting up your own test automation environment
  21. Server-side website programming
  22. First steps
    1. First steps overview
    2. Introduction to the server-side
    3. Client-Server overview
    4. Server-side web frameworks
    5. Website security
  23. Django web framework (Python)
    1. Django web framework (Python) overview
    2. Introduction
    3. Setting up a development environment
    4. Tutorial: The Local Library website
    5. Tutorial Part 2: Creating a skeleton website
    6. Tutorial Part 3: Using models
    7. Tutorial Part 4: Django admin site
    8. Tutorial Part 5: Creating our home page
    9. Tutorial Part 6: Generic list and detail views
    10. Tutorial Part 7: Sessions framework
    11. Tutorial Part 8: User authentication and permissions
    12. Tutorial Part 9: Working with forms
    13. Tutorial Part 10: Testing a Django web application
    14. Tutorial Part 11: Deploying Django to production
    15. Web application security
    16. Assessment: DIY mini blog
  24. Express Web Framework (node.js/JavaScript)
    1. Express Web Framework (Node.js/JavaScript) overview
    2. Express/Node introduction
    3. Setting up a Node (Express) development environment
    4. Express tutorial: The Local Library website
    5. Express Tutorial Part 2: Creating a skeleton website
    6. Express Tutorial Part 3: Using a database (with Mongoose)
    7. Express Tutorial Part 4: Routes and controllers
    8. Express Tutorial Part 5: Displaying library data
    9. Express Tutorial Part 6: Working with forms
    10. Express Tutorial Part 7: Deploying to production
  25. Further resources
  26. Advanced learning material
    1. WebGL: Graphics processing
  27. Common questions
    1. HTML questions
    2. CSS questions
    3. JavaScript questions
    4. How the Web works
    5. Tools and setup
    6. Design and accessibility
  28. How to contribute