Advantages of Using JavaScript in Web Development
As one of the most popular programming languages on the internet, javascript has many uses. It is a scripting language that can be used to make websites interactive and dynamic. Along with hypertext markup language (HTML) and cascading style sheets (CSS), it forms the foundation of web development. Its unique feature is that it can be executed directly in a user’s browser without the need for downloading an additional program.
The code is written in plain text, which makes it easy for anyone to read and understand. In contrast, other programming languages need to be compiled to be executable. JavaScript is interpreted by a type of program called a parser, and this is provided by most web browsers. As such, it’s very fast to execute and is also more portable than other languages.
Unlike other languages that use a purely procedural approach, javascript is object-oriented. It has a large library of functions that can be used to create complex applications and to perform common tasks. This makes it a very powerful and flexible tool to have in your arsenal as a developer.
The other advantage of javascript is that it allows developers to easily modify HTML and CSS on the fly. This is very useful for displaying real-time information on a website such as stock or crypto prices, weather updates or live product availability. It is also used to add interactivity to a webpage such as a chat widget or an online game.
JS is often used for front end web development, but it can be utilized across the full stack of web architecture as well. This includes back-end services like web analytics, event tracking and even ad serving.
It’s important to note that javascript needs to be loaded before the HTML that it will be modifying is processed by the browser. If not, errors can occur during execution. This can be resolved by using a script loader such as async or defer.
Async will download the script without blocking the page from being rendered while it is being fetched. However, it won’t be executed until all the other scripts on the page have been parsed and DOM content is in place. Therefore, it’s best to use async when your scripts don’t have any dependencies on other scripts.
It is also possible to use a function loader such as defer, which will only load and execute your script once all the other scripts on the page have finished loading and parsing. However, it’s generally not a good idea to pollute your HTML with these function loaders as it’s bad practice and inefficient for the browser to have to wait until all of the page’s content has been loaded before running your javascript. A more efficient method is to use an event listener that will fire when the DOMContentLoaded is fired in the browser. This is discussed further in the Script Loading Strategies section below.