Explain like I only speak in plain English

jQuery is a JavaScript library that helps front-end web engineers add interactive features to a website. In essence, it is a collection of commonly used stand alone tools that front-end engineers use to build websites.

Since many engineers end up building similar things, someone decided to package those custom tools into a library, and named it jQuery. jQuery is a collection of tools that extends pure JavaScript and makes web engineers' lives easier.

All the tools in jQuery are written in pure JavaScript. Most of the jQuery tools just carry out trivial tasks but those tools are not available in standard JavaScript. You can create the tools yourself if you want, and not use jQuery. But using jQuery can reduce the size of your program and development time drastically.

Explain like I'm a total nerd

jQuery was first released in 2006 by John Resig. It is now a staple amongst front-end web engineers and one of the first libraries beginners should learn when they pick up front-end web development.

jQuery is present in 73.2% of all websites surveyed in this report. BuiltWith ranks jQuery as the top used JavaScript library for top million sites with 14% coverage.

jQuery's tool box includes DOM selection, DOM manipulation, Events, Animations, Ajax and more. Most engineers will call the jQuery library using its alias `$` instead of its actual variable name `jQuery`.

Explain like I'm an artist

Using jQuery for development is like using rulers, compass, and templates when sketching versus doing it all free hand. jQuery assists engineers by providing them an array of tools to help them do trivial tasks easier. Instead of drawing a straight line free hand, they use a ruler. Instead of drawing circles free hand, they use a compass.

Explain like I like examples

jQuery can help reduce the amount of code we write drastically. The following code adds a paragraph to the beginning of a container. In pure JavaScript, it would require 7 lines of code. Using jQuery reduces it to 1 line of code.

var container = document.body.querySelector("#container");
var p = document.createElement('p');
p.innerHTML = 'Hello World';
var prependChild = function(newNode) {
  this.insertBefore(newNode, this.firstChild);
}
prependChild.call(container, p);

With jQuery

$('#container').prepend('<p>Hello World</p>');

Explain like I already know it

With the increase in popularity of React, Angular and other more opinionated front-end frameworks. jQuery is no longer the first choice for new projects. However, for simple websites, jQuery would probably still be good as its setup cost is much lower.

When using jQuery with other JavaScript libraries that uses the `$`. It would be wise to run jQuery in no-conflict mode.

We also need to remember that jQuery events are synthetic events and might not have the exact same behavior as native browser events. You can inspect the original browser event through `event.originalEvent`.

JavaScript

JavaScript can turn static websites into dynamic websites. JavaScript gives possibility to interactive features such as live chat, infinite feed loading, map navigation, animation and more. If HTML is the skeleton, CSS is the skin/fat/hair, JavaScript would be the muscles.

Library

In programming, a library is a collection of programs that perform specific tasks. Engineers incorporate libraries into their projects so they don't have to write the programs themselves, to save development time.