For such uses-cases, here's how it's done: You may want to have your JavaScript code in a different file.

Just like the style tag for style declarations within an HTML page, the script tag exists for JavaScript. The value of onclick can be some Match calculation, a dynamic addition to the DOM – any syntax-valid JavaScript code. Here, you have the JavaScript code in HTML tags in some special JS-based attributes.įor example, HTML tags have event attributes that allow you to execute some code inline when an event is triggered.

Just like with CSS, JavaScript can be used in HTML in various ways, such as: 1. But to get you started with JS, we'll look at: JavaScript can do a lot more than what I can cover in this article. You cannot get this with HTML, CSS, nor both of them together. In the codepen, you'll see that as you type in the input field, the text shows on the screen. JavaScript, on the other hand, is a dynamic programming language that supports Math calculations, allows you to dynamically add HTML contents to the DOM, creates dynamic style declarations, fetches contents from another website, and lots more.īefore we go into how JavaScript does all of these things, let's look at a quick example. HTML and CSS are often called markup languages rather than programming languages, because they, at their core, provide markups for documents with very little dynamism. CSS declares various styles for the contents provided on the web document. HTML defines the structure of your web document and the content therein. 90% (if not more) of your webpages would be static, and you'd only have the dynamic changes like animations that CSS provides. These alone limit you to a few web page implementations. Without JavaScript, all you would have on the web would be HTML and CSS. What Would the Web Look Like Without JavaScript? Any time you see a click-to-show dropdown menu, extra content added to a page, and dynamically changing element colors on a page, to name a few features, you're seeing the effects of JavaScript. Many browsers use JavaScript as a scripting language for doing dynamic things on the web. It allows you to implement dynamic features on web pages that cannot be done with only HTML and CSS. JavaScript is a dynamic programming language that's used for web development, in web applications, for game development, and lots more.

What is this in javascript