What is JavaScript and what is it used for?

Imagine a world in which websites are rigid and passive. No clicks, no animations, no interactive elements - just static text and images. Sounds boring, doesn't it? Fortunately, we don't live in that world!

But what is JavaScript and how does it work? Let's take a look at the most important questions and how it is used in practice.

What is JavaScript?

JavaScript is a scripting language that is used to extend HTML pages. It enables the implementation of dynamic and interactive elements on websites. These are, for example, forms, click events and data retrieval.

Netscape developed the language in 1995 to extend HTML as a pure markup language. Originally published under the name "LiveScript", JavaScript - or simply "JS" - quickly established itself as the standard in web development.

What is JavaScript used for?

The possible use cases are diverse and extend far beyond the classic area of application in the user's browser. The following examples illustrate the wide range of possible use cases:

Interactive elements

• Validate forms and send data to the server
• Hamburger menus and other interactive menus
• Creation of animations and visual effects
• Browser games

Dynamic content

News feeds, live tickers or chat applications use JS for real-time information without having to reload the page.

Browser APIs

Functions such as geolocation of the user, access to the webcam or control of media players are possible with JS.

Server-side applications

In combination with server-side technologies such as Node.js, JavaScript can also be used for the development of applications such as interfaces (APIs).

How does JavaScript work?

Web browser

When JavaScript code is embedded in the HTML code of a website, it is interpreted by the user's browser. This is done with the help of a JavaScript engine that executes the code line by line and performs the corresponding actions.

Server

For applications for which no browser is available, there are runtime environments such as Node.js, Deno or bun.sh. These can be installed on web servers and make the code executable.

JavaScript libraries

Thanks to the open source community, there are a number of free libraries for recurring functions and logic. These are collections of predefined functions and code blocks, but also entire frameworks.

They offer a variety of reusable components and modules that simplify and standardize frequently required tasks.

This not only saves development time, but is also widely and well documented thanks to the community.

The best-known library is probably jQuery. Popular frameworks are React, Angular and Vue.js.

JavaScript benefits: When is JavaScript suitable for a project?

Anyone who insists on scalable and high-performance web solutions that meet the requirements of modern web applications should definitely look into JavaScript.

Of course, PHP still has its right to exist as the language in the web sector. However, JS has developed into a mature and, above all, fully-fledged programming language over the last few years. Robust server applications can usually be developed faster and more agile than PHP. The times when JavaScript was only used to manipulate simple user actions in the browser are certainly over.

JS is particularly popular among young developers. This is why there will be no shortage of developers who are proficient in the language in the near future.

The language is also constantly being further developed and equipped with new functions that further expand the possibilities for web developers. With the growing demand for dynamic and interactive web applications, JavaScript will continue to play an important role in web development in the coming years.