Theory of JavaScript 2023

What is JavaScript?

JavaScript is a programming language that has revolutionized the way we interact with the web. It is like a swiss-army knife, which can be used to build all kinds of applications from web apps, servers, A.I, databases, IoT, or mobile apps.

It's the easiest language to learn for beginners but also the trickiest for experts. You need to know all kinds of stuff to use this language to an expert level.

As the web continues to evolve and become more complex, the demand for skilled JavaScript developers is only set to grow. With its versatility and accessibility, JavaScript is likely to remain one of the most important programming languages for years to come, enabling developers to create rich and engaging web experiences for users all over the world.

The History of JavaScript

It was created in 1993 by Brenden Eich at Netscape, at that time the world wide web has just begun its global domination, the internet connects people to people from all over the world via cable.

At that time, websites were built purely by HTML. JavaScript was designed as an easy-to-use high-level language to help developers add interactions to their websites. Today, it's arguably the most famous language for the future of tech, and its standard implementation is called EcmaScript (ES), and it's the only code that runs in the web browser besides Web Assembly.

At its core, JavaScript is a scripting language designed to add interactivity to web pages. It is a lightweight language that runs within the browser, allowing developers to add functionality to their web pages without the need for server-side processing. By allowing web pages to interact with the user, JavaScript has opened up a whole new world of possibilities, enabling the creation of rich, interactive user interfaces and web applications.

How JavaScript Works?

JavaScript is a high-level scripting language used to create interactive web pages and web applications. It is executed on the client-side, meaning that it runs in the user's browser, rather than on a server. The V8 engine, which is developed by Google, is a powerful JavaScript engine that provides a high-performance runtime environment for executing JavaScript code.

However the browser is not only the runtime environment, you can also run JavaScript in the server thanks to tools such as Node.js and Deno. Besides JavaScript is a scripting language, which means you can run JS on the fly using the Devtool in the browser.

JavaScript is a scripting language, which means that it is interpreted and executed by the browser or server environment, rather than being compiled into an executable program. This makes it a highly flexible and dynamic language, allowing developers to make changes to code and see the results immediately, without the need to compile and run a new version of the code.

JavaScript is interpreted line by line in contrast to other languages like C which is compiled via a compiler. Under the hood, there's V8 Engine which runs JavaScript directly on the browser with a process called just-in-time compilation (JIT).

Summary

In summary, JavaScript is a high-level scripting language that is executed on the client-side or server-side, with the V8 engine providing a high-performance runtime environment for executing JavaScript code. The V8 engine includes a JIT compiler that dynamically compiles JavaScript code into native machine code, optimizing performance and improving execution speed. As a scripting language, JavaScript is highly flexible and dynamic, allowing developers to make changes to code and see the results immediately.