A Beginner’s Guide to JavaScript

javascript is a computer programming language that is used to add functionality to websites and web applications. It is often used to create interactive elements like animations, pop-up windows, search bars, audio and video, chat widgets, and in-browser games. JS also allows for real-time updates to a website without the need for a full page reload. Websites that display live stock or crypto prices, real-time product availability, and news tickers are all built using JS.

The first step in learning javascript is to understand the syntax. This includes understanding the difference between function definitions and method calls, object variables, and nested functions. These concepts may seem intimidating to the new developer, but they will come naturally with time and practice.

All JS code is run in the context of an execution environment called an execution context (EC). This environment contains a set of global variables that are shared between functions, and it provides an initial value for a variable when it executes. The EC is also where functions are invoked and returned to. Functions can also be created in the EC and then bound to a specific context with the bind method. This is how a function can take the input of other nested functions or pass it to another function for execution.

It’s important to note that javascript is used for client-side code, and most web browsers have built-in JS engines that run it when you visit a website. This is where JS is most commonly used, although it is increasingly being used to make server-side web applications as well.

Unlike other major computer languages, which are mostly used for either server or client-side programming, javascript is widely used across a variety of application areas. This makes it a great foundational language to learn before moving on to other frameworks and libraries.

As the most widely-adopted browser language, it has been fully integrated into HTML/CSS, and many other languages get “transpiled” to JavaScript to provide some additional functionality. As a result, a knowledge of JavaScript opens the door to a variety of career options in front-end and back-end web development as well as full stack development.

While you can write a website or web app entirely in javascript, it’s much more efficient to use a library like jQuery to perform the same tasks. This will save you a lot of time and effort, and it will help you create more concise and cleaner code.

Unlike other computer programming languages, javascript is mostly used for client-side web applications, meaning it’s used to add features to web pages and web apps that are viewed in a web browser. This includes things like adding navigation menus, file upload forms, and in-browser games. It’s also useful for displaying real-time data on a webpage, such as stock or currency prices, weather forecasts, and sports scores. Almost all of the major internet companies use javascript to add functionality to their sites and apps. For example, Facebook and Google both have news feeds and video chat applications that use javascript.