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Async vs Defer - Which Script Tag Attribute is More Efficient when Loading JavaScript?

JavaScript is the most popular language in the world. Why? Because it's the only well-adopted language supported by Web Browsers that brings dynamics to the frontend experience.

Because of that, almost any web application requires developers to write at least a bit of JavaScript code. While it's not a problem (unless you hate this language 😉), some of us tend to create very complex, frontend-heavy applications that load.. well, definitely not fast.

In this article, you'll get familiar with async and defer - two script tag attributes that will speed up your website's rendering.