EDWIN MORCILLOS YU

What is JavaScript?

JavaScript often abbreviated as JS, is a programming language and core technology of the World Wide Web, alongside HTML and CSS. 99% of websites use JavaScript on the client side for webpage behavior, often incorporating third-party libraries. All major web browsers have a dedicated JavaScript engine to execute the code on users' devices.

JavaScriptis a high-level, often just-in-time compiled language that conforms to the ECMAScript standard. It has dynamic typing, prototype-based object-orientation, and first-class functions. It is multiparadigm, supporting event-driven, functional, and imperative programming styles. It has application programming interfaces (APIs) for working with text, dates, regular expressions, standard data structures, and the Document Object Model (DOM).

The ECMAScript standard does not include any input/output (I/O), such as networking, storage, or graphics facilities. In practice, the web browser or other runtime system provides JavaScript APIs for I/O.

JavaScript engines were originally used only in web browsers, but are now core components of some servers and a variety of applications. The most popular runtime system for this usage is Node.js.

Although Java and JavaScript are similar in name, syntax, and respective standard libraries, the two languages are distinct and differ greatly in design.

Website Client-side Usage

JavaScript is the dominant client-side scripting language of the Web, with 99% of all websites using it for this purpose.[10] Scripts are embedded in or included from HTML documents and interact with the DOM.

All major web browsers have a built-in JavaScript engine that executes the code on the user's device.

Examples of Scripted Behavior

• Loading new web page content without reloading the page, via Ajax or a WebSocket. For example, users of social media can send and receive messages without leaving the current page.
• Web page animations, such as fading objects in and out, resizing, and moving them.
• Playing browser games.
• Controlling the playback of streaming media.
• Generating pop-up ads or alert boxes.
• Validating input values of a web form before the data is sent to a web server.
• Logging data about the user's behavior then sending it to a server. The website owner can use this data for analytics, ad tracking, and personalization.
• Redirecting a user to another page.
• Storing and retrieving data on the user's device, via the storage or IndexedDB standards.

Web Libraries and Frameworks

React(also known as React.js or ReactJS) is a free and open-source front-end JavaScript library for building user interfaces based on components. It is maintained by Meta (formerly Facebook) and a community of individual developers and companies.

Reactcan be used to develop single-page, mobile, or server-rendered applications with frameworks like Next.js. Because React is only concerned with the user interface and rendering components to the DOM, React applications often rely on libraries for routing and other client-side functionality. A key advantage of React is that it only rerenders those parts of the page that have changed, avoiding unnecessary rerendering of unchanged DOM elements.

Angular

Angular (also referred to as "Angular 2+") is a TypeScript-based, free and open-source single-page web application framework led by the Angular Team at Google and by a community of individuals and corporations. Angular is a complete rewrite from the same team that built AngularJS.

jQuery

In 2012, jQuery was by far the most popular client-side library, used by over 75% of websites. While still in widespread use, its popularity has been surpassed by newer libraries and frameworks.

Vanilla JS

The framework-like moniker "Vanilla JS" is term that has been coined for websites not using any libraries or frameworks at all, instead relying entirely on standard JavaScript functionality.

By doing a lot of practice, you will definitely experience errors and bugs in your code, but don't worry, you will overcome them all!

Subscribe to Our Newsletter