Using the form validation plugin

Plugins written by other developers can be searched and downloaded from the central plugin repository at https://plugins.jquery.com. On searching for the validation keyword, we come across the jQuery validation plugin written in 2006 by Jörn Zaefferer, a member of the core jQuery team. The official site of the plugin is at http://jqueryvalidation.org.

In this example, let's download and use this plugin in our application. The programming constructs used in this example are summarized as follows:

Construct	Type	Description
$("#identifier")	jQuery selector	This selects an element based on its ID.
$("html_tag")	jQuery selector	This selects all elements with the specified HTML tag.
click	jQuery event	This is fired when you click on an element. It corresponds to the JavaScript click event.
.closest()	jQuery method	For each matched element, this returns the first element that matches the selector by traversing up the DOM tree.
event.preventDefault...