What is jQuery?
jQuery is an open-sourced JavaScript library that simplifies creation and navigation of web applications. Specifically, jQuery simplifies HTML Document Object Model (DOM) manipulation, Asynchronous JavaScript and XML (Ajax) and event handling. Additionally, jQuery incorporates JavaScript functionalities by manipulating CSS properties to add effects such as fade-ins and outs for website elements. jQuery is a widely used JavaScript library and is supported by thousands of user-created plug-ins.
jQuery will simplify DOM manipulation by allowing users to find, select and manipulate elements with specific properties. Users can also change element attributes and respond to events. jQuery can use Ajax to pass data between browsers and the servers without having to reload the web page. Event handling is provided by an event handler which receives an object upon an event. The event handler specifies the type of event and executes a DOM element function to prevent the event’s effect. The syntax for these simplicities is provided through jQuery’s selector engine, Sizzle. Sizzle is a CSS selector engine which can run through DOM elements to find specified elements.
Features
Features provided by jQuery include:
- A light footprint around 30 kB.
- Supports Chrome, Firefox, Safari, Internet Explorer and Edge.
- Event handling
- Ajax support
- Plug-in support
- DOM element manipulation based on CSS selectors.
- JSON parsing
- Feature detection
- Animation effects
jQuery plugins
jQuery supports plug-ins which provide additional functionality to jQuery. Plug-ins are added on top of JavaScript libraries. They can be used to extend a prototype element, which enables jQuery to use added features.
Functions which plug-ins provide include XML tools, cookie handling, table sorting, Ajax helpers, drag and drop functionalities, and form validation. End-users can create and execute their own plug-ins or can freely make them available to others who may benefit from their use. The jQuery team also maintains some plug-ins. Plug-ins can be found on a GitHub-hosted repository.
