JavaScript is a client-side scripting language that extends the functionality of websites by modifying or generating content. Developers use JavaScript to create interactive websites, from updating social media feeds to displaying animations and interactive maps.
The code can be integrated into HTML pages in various ways, such as in external files or as parameters of HTML tags. Careful integration is important to avoid errors that could lead to bugs and have a negative impact on search engine optimization. Originally developed as a browser-side technology, JavaScript makes web applications more dynamic by responding to user interactions and changing the layout of the website. With further development, libraries, frameworks and programming practices are also used outside of web browsers.
Today, JavaScript can be used for both client-side and server-side development. The possible applications of JavaScript are diverse, from counting page visits to displaying monthly calendars and checking form entries. Examples range from calculators to the implementation of shopping baskets in web stores. CommonJS serves as an extension of JavaScript and enables programming interfaces for applications such as databases, web services and desktop applications.