when a web page is loaded in a browser, the code (HTML, CSS, and JavaScript) is executed within the browser tab, which acts like a factory that takes in the code and produces the web page. One common use of JavaScript is to change the HTML and CSS in order to update the user interface using the Document Object Model API. It is important to note that the code is generally loaded and executed in the order it appears on the page and errors may occur if JavaScript is run before the related HTML and CSS. 

What is JavaScript doing on your page?

React is a user interface library that was created by Jordan Walke at Meta. It was first deployed on Facebook's News Feed in 2011 and later on Instagram in 2012. 

React is based on components, allowing you to divide views into smaller pieces of logic and view, and reuse them. React is declarative, allowing you to create simple views and React will render them efficiently. Data is passed in one direction. React has many features such as the Virtual DOM, Lifecycle Methods, JSX, and React Hooks.

React Js

React documentation

JavaScript is case-sensitive and uses the Unicode character set. An instruction is called a statement. We can separate statements with a semicolon, although it is not required if a statement is on one line.

The basic concepts in JavaScript include: 
- Comments
- Declarations
- Variables
- Data structures and types
- Literals

Grammar and types

https://developer.mozilla.org/en-US/docs/Web/JavaScript/Guide/Grammar_and_types

JavaScript - Grammar and types

Node.js, created by Ryan Dahl and first released in 2009, is an open-source server environment designed to run on multiple platforms, including Windows, Linux, Unix, and macOS. It is a back-end JavaScript runtime environment that uses the V8 JavaScript engine to execute JavaScript code outside of a web browser. With Node.js, developers can create command-line tools and server-side scripts using JavaScript. By enabling scripts to run server-side, Node.js allows for the creation of dynamic web page content before it is sent to the user's browser. This approach unifies web application development by promoting the use of a single programming language across both server-side and client-side scripts.

Node.js

Eloquent JavaScript

JavaScript is a lightweight, interpreted or just-in-time compiled, programming language with first-class functions. It is a prototype-based, multi-paradigm, single-threaded, dynamic language that supports object-oriented, imperative, and declarative programming styles, such as functional programming. It was invented by Brendan Eich in 1995 at Netscape and later continued to be developed under the ECMA standard by the Mozilla Foundation.

University of Michigan - Ann Arbor

There are many languages that follow the OOP paradigm either partially or completely. Some of these languages include:
- Rust
- C++
- Python
- Go
- Java
- Javascript
- Php

Object-Oriented Programming (OOP) Languages

https://developer.mozilla.org/

Python is an interpreted, object-oriented, high-level programming language. It's known for its built in data structures and robust libraries. Despite this, Python was developed to have an easy to learn syntax which emphasizes readability and whitespace. Python supports modules and packages, which encourages program modularity and code reuse. The Python interpreter and standard library are available without charge for all major platforms, and can be freely distributed.

Python Programming Language

C++ is an efficient ,flexible and portable object oriented language.

C++ Programming Language

Rust is a compiled, multi-paradigm, general purpose programming language with a focus on reliability and safety. Rust boasts a rich type system and ownership model that guarantees memory and thread safety, eliminating multitudes of bugs at compile time.

Rust Programming Language

PHP is a `general-purpose scripting language` that widely used in web development. Known for its speed, adaptability, and practicality, it drives a range of websites, from personal blogs to some of the biggest and most visited sites on the internet.

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