fundamentals of the jQuery library

1、why is jquery

Only 32kB minified and gzipped. Can also be included as an AMD module

Supports CSS3 selectors to find elements as well as in style property manipulation

IE, Firefox, Safari, Opera, Chrome, and more



2、Downloading jQuery using Bower

jQuery is registered as a package with Bower. You can install the latest version of jQuery with the command:

bower install jquery

This will install jQuery to Bower's install directory, the default being

bower_components

. Within

bower_components/jquery/dist/

you will find an uncompressed release, a compressed release, and a map file.
if you wish to install just the compressed jQuery 2.1.0, you can install just that file with the following command:

bower install http://code.jquery.com/jquery-2.1.4.min.js[/code] 
3、Using jQuery with a CDN

CDNs can offer a performance benefit by hosting jQuery on servers spread across the globe. This also offers an advantage that if the visitor to your webpage has already downloaded a copy of jQuery from the same CDN, it won't have to be re-downloaded.



<script src="//code.jquery.com/jquery-1.11.3.min.js"></script>
<script src="//code.jquery.com/jquery-migrate-1.2.1.min.js"></script>


To see all available files and versions, visit http://code.jquery.com

4、References：
http://jquery.com/
https://github.com/jquery/jquery
http://plugins.jquery.com/

5、plugins with AMD

/*==============jquery插件queue.js，符合AMD规范============*/

define( [
"./core",
"./data/var/dataPriv",
"./deferred",
"./callbacks"
], function( jQuery, dataPriv ) {

jQuery.extend( {
queue: function( elem, type, data ) {
//...
},

dequeue: function( elem, type ) {
//...
},

// Not public - generate a queueHooks object, or return the current one
_queueHooks: function( elem, type ) {
//...
}
} );

jQuery.fn.extend( {
queue: function( type, data ) {
//...
},
dequeue: function( type ) {
return this.each( function() {
jQuery.dequeue( this, type );
} );
},
clearQueue: function( type ) {
return this.queue( type || "fx", [] );
},

// Get a promise resolved when queues of a certain type
// are emptied (fx is the type by default)
promise: function( type, obj ) {
//...
}
} );

return jQuery;
} );

/*=============core.js==================*/
define( [
"./var/arr",
"./var/document",
"./var/slice",
"./var/concat",
"./var/push",
"./var/indexOf",
"./var/class2type",
"./var/toString",
"./var/hasOwn",
"./var/support",
"./core/DOMEval"
], function( arr, document, slice, concat,
push, indexOf, class2type, toString, hasOwn, support, DOMEval ) {

var
version = "@VERSION",

// Define a local copy of jQuery
jQuery = function( selector, context ) {

// The jQuery object is actually just the init constructor 'enhanced'
// Need init if jQuery is called (just allow error to be thrown if not included)
return new jQuery.fn.init( selector, context );
},

// Support: Android<4.1
// Make sure we trim BOM and NBSP
rtrim = /^[\s\uFEFF\xA0]+|[\s\uFEFF\xA0]+$/g,

// Matches dashed string for camelizing
rmsPrefix = /^-ms-/,
rdashAlpha = /-([a-z])/g,

// Used by jQuery.camelCase as callback to replace()
fcamelCase = function( all, letter ) {
return letter.toUpperCase();
};

jQuery.fn = jQuery.prototype = {

// The current version of jQuery being used
jquery: version,

constructor: jQuery,

// The default length of a jQuery object is 0
length: 0,
// Execute a callback for every element in the matched set.
each: function( callback ) {
return jQuery.each( this, callback );
},

map: function( callback ) {
return this.pushStack( jQuery.map( this, function( elem, i ) {
return callback.call( elem, i, elem );
} ) );
}
};

jQuery.extend = jQuery.fn.extend = function() {
//...
};

jQuery.extend( {

// Unique for each copy of jQuery on the page
expando: "jQuery" + ( version + Math.random() ).replace( /\D/g, "" ),

// Assume jQuery is ready without the ready module
isReady: true,

error: function( msg ) {
throw new Error( msg );
}
} );

return jQuery;
} );