JavaScript
JavaScript is a cross-platform, object-oriented scripting language used to make webpages interactive (e.g., having complex animations, clickable buttons, popup menus, etc.). There are also more advanced server-side versions of JavaScript such as Node.js, which allow you to add more functionality to a website than downloading files (such as real-time collaboration between multiple computers). Inside a host environment (for example, a web browser), JavaScript can be connected to the objects of its environment to provide programmatic control over them.
Classes & Objects
Classes are a template for creating objects. They encapsulate data with code to work on that data. Classes in JS are built on prototypes but also have some syntax and semantics that are not shared with ES5 class-like semantics.
this
In most cases, the value of this is determined by how a function is called (runtime binding). It can’t be set by assignment during execution, and it may be different each time the function is called.
Closure
A closure is a combination of a function bundled together (enclosed) with references to its surrounding state (the lexical environment). In other words, a closure gives you access to an outer function’s scope from an inner function. In JavaScript, closures are created every time a function is created, at function creation time.
Callbacks and promises
A promise is an object representing the eventual completion or failure of an asynchronous operation. Since most people are consumers of already-created promises, this guide will explain the consumption of returned promises before explaining how to create them. Essentially, a promise is a returned object to which you attach callbacks, instead of passing callbacks into a function.
Version controlling
What is version control?
The method of recording and controlling changes to software code is known as version control, sometimes known as source control. Version control systems (VCS) are software tools that aid software development teams in managing source code change over time.
Git
For most development teams today, Git is the best option. While each team is unique and should conduct its own analysis, the following are the primary reasons why Git version control is chosen over other options: