JavaScript is a high-level, interpreted, and dynamic programming language. It was originally created by Brendan Eich back in 1995, with the initial purpose of providing interactivity to web pages.
Initially, JavaScript was intended to manipulate elements on web pages and perform client-side validations. At that time… as a programming language, it was rather poor, to be honest.
Given the evolution of the web, new needs for JavaScript soon emerged. In this way, JavaScript has evolved considerably, becoming a “more formal” and standardized language.
This is how ECMAScript appeared, which is the standard on which the JavaScript programming language is based. Successively, the different versions have added functionalities to the language.
Currently, JavaScript has evolved significantly, becoming a cross-platform, multipurpose, and multi-paradigm language, and one of the most important programming languages.
JavaScript Features
JavaScript is an interpreted language, which means that the code is executed line by line at runtime, without the need for a previous compilation stage.
On the other hand, JavaScript is a dynamically typed language, which means that variables are not associated with specific data types. You can assign different data types to the same variable during program execution.
In addition, it is an object-oriented language, which means that it is based on the concept of objects and classes. However, its object model is different from that of traditional languages such as Java or C++, as it is based on prototypes instead of classes.
Finally, JavaScript is also a functional language. This means that functions are first-class citizens, being able to be assigned to variables, passed as arguments, and returned as values.
Where JavaScript is Used
Today, JavaScript is truly cross-platform and multipurpose. Although, logically, it is still associated with web development in many cases.
JavaScript is used in a variety of applications and contexts in web development, such as DOM manipulation, form validation, communication, animations, and graphic effects. In general, everything that has to do with providing dynamic behavior to a web application.
But, JavaScript is not solely restricted to web browsers. Currently, there are JavaScript runtime environments such as Node.js or Deno, which allow us to execute a JavaScript program on a computer or server.
It is also possible to embed web pages in desktop applications, for example with frameworks like Electron. Or create mobile applications with libraries like React Native.
It is even possible to use it on devices such as Arduino or an ESP32, with projects like Johnny-Five, to create electronics and IoT (Internet of Things) applications.
In short, you can currently run JavaScript in almost any place, and it has become one of the most important languages to know.