JavaScript is a scripting language that is mostly used in web development. JavaScript runs in the front-end, so it can update HTML elements, connect to a server (e.g Database server, File Server etc.), change page style (CSS) and more.
You can learn JavaScript here: https://www.learn-js.org/
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JavaScript in HTML file
HTML has the <script> tag, which allows scripts in a web page.
Example:
<!DOCTYPE html><html><head><title>JavaScript</title></head><body> <p>Hello, JavaScript!</p></body><script>console.log("Hello World!");</script></html>"Hello World!" will show in your browser's console.
External JavaScript
You can import a JavaScript (.js) file. This is useful for organizing your website.
JS File (example.js):
console.log("Hello World!");HTML File:
<!DOCTYPE html><html><head><title>External JavaScript</title></head><body><p>External JavaScript!</p></body><script src=example.js></script></html>The src attribute, imports the specified JavaScript file.
Also the src attribute, can import scripts from a CDN (Content Delivery Network). That is mostly used for including JavaScript libraries.
<!DOCTYPE html><html><head><title>External CDN JavaScript</title></head><body><p>External CDN JavaScript!</p></body><script src=https://ajax.googleapis.com/ajax/libs/jquery/3.5.1/jquery.min.js></script></html>The type attribute
The <script> tag has the type attribute, which specifies the scripting language that is going to be used in the <script> tag. Now it's almost obsolete. JavaScript is the default.
They would use this in the HTML4 days:
<html><head><title>Other scripting languages</title></head><body><p>Other scripting languages</p></body><script type=text/javascript>console.log("Hello World");</script></html>Do it Yourself
- Add JavaScript code after
</body>. The code must bealert("Hello World!");(This will popup "Hello World!")
