What is JavaScript? The dynamic programming language for websites, explained

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Web developers use JavaScript to enhance the websites we visit every day. Luis Alvarez/Getty Images
  • JavaScript is a text-based programming language that’s commonly used to make webpages more dynamic and interactive for visitors.
  • JavaScript offers functionality for features such as image carousels, playing media on a webpage, and displaying countdowns and timers.
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While you may not be actively aware of it, JavaScript is used in nearly every website on the internet these days. It’s a programming language that is simple to learn and incredibly versatile.

What is JavaScript?

JavaScript is a text-based, object-oriented programming language used to make webpages and apps more dynamic and interactive for visitors.

Used on both the client and server side, JavaScript offers enhanced abilities that basic languages like HTML and CSS can’t, such as refreshing a Twitter feed, embedded YouTube videos, and more. In other words, JavaScript-enhanced webpages are more dynamic and user-focused, which can keep users coming back to the site.

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Both developers and website visitors benefit from Javascript. Maskot/Getty Images

That said, JavaScript is meant to be used with other programming languages rather than as a replacement for them.

For instance, websites and apps will still need to use HTML for basic structure, while CSS is required for formatting and layout preferences as well as controlling how the text, images, and other content on a webpage is presented. From there, JavaScript can enhance those elements, taking them from being static features to interactive and exciting ones.

What JavaScript is used for

  • Javascript allows webpages to become more interactive in many ways including displaying animations, making functional drop-down menus, zooming in and out of webpage images, or even changing button colors when the user’s mouse hovers over it.
  • Developers often use JavaScript frameworks such as Vue, React, and Angular when creating web and mobile apps as they allow the use of routine tasks and features that many apps have in common. These features include search buttons and category selection options, just to name a few.
  • JavaScript is widely used in game development, particularly for new developers who want to practice and refine their skills.
  • Some developers also choose to use Node.js, a back-end JavaScript infrastructure, to create basic web servers and to build on a site’s infrastructure.

The advantages of using JavaScript

  • Interactivity: JavaScript websites are more interactive and appealing to users since the language creates richer and more attractive interfaces.
  • Speed: Websites will load and operate at higher speed since JavaScript can be run immediately in the browser, thereby reducing demand on the server.
  • Ease: It’s simple to implement and often takes only a basic level of knowledge to utilize.
  • Integration: JavaScript works well with most other programming languages, making it possible to integrate into a host of different applications.
  • Popularity: It’s incredibly popular – most websites use JavaScript in some form regardless of the nature of the website.

There aren’t many disadvantages to using JavaScript; the primary issue is that there is the potential for client-side security breaches in Javascript code, since it’s viewable to users. Despite that, Javascript remains the most popular programming language at the moment, and given that it’s a native programming language for web browsers, it’s worth it for new programmers to learn the basics and use them in projects.

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