JavaScript Tutorial for Beginners
JavaScript adds behavior and interactivity to web pages. Start with values and variables, then learn how to organize reusable instructions and respond to user actions.
JavaScript runs in the browser and can update page content, respond to clicks, validate forms and work with data. It works alongside HTML for structure and CSS for presentation.
Add JavaScript to a web page
Link an external JavaScript file with defer so the browser runs it after parsing the HTML:
<script src="script.js" defer></script>Start with these JavaScript topics
Variables and valuesStore text, numbers and other data.
FunctionsGroup reusable instructions into named actions.
DOM and eventsFind page elements and respond to user interaction.ConditionalsChoose what your code does based on a condition.
ArraysStore and work through ordered lists of values.
ObjectsGroup related information into named properties.
Async and fetchRequest data and handle asynchronous results.
Open your browser's developer tools and use the Console to see messages and diagnose JavaScript errors.