jQuery("#soyUnElemento").show();
jQuery("#soyUnElemento").hide();

jQuery(".elementosClick").click(function(){ jQuery("#soyUnElemento").hide(); });

<script type="text/javascript" src="jquery.js"></script>

<script type="text/javascript" src="http://ajax.microsoft.com/ajax/jquery/jquery-1.4.2.min.js"></script>

<script type="text/javascript" src="http://code.jquery.com/jquery-1.4.2.min.js"></script>

jquery("*")

jQuery("div")

jQuery("div.entrada")

jQuery("div#cabecera")

jquery("p,div,a")

jquery("a[rel]")

jquery("a[rel='nofollow']")

jQuery("a[rel!='nofollow']")

jquery("a[href^='http://infrabios.com/']")

jquery("a[href$='.com']")

jquery("a[href*='Bios']")

jquery("a[rel='nofollow'][href]")

jquery(":button")

jquery(":checkbox")

jquery(":file")

jquery(":header")

jquery(":image")

jquery(":input")

jquery(":password")

jquery(":radio")

jquery(":reset")

jquery(":select")

jquery(":submit")

jquery(":text")

jquery(":checked")

jquery("input:enabled")

jquery("input:disabled")

jquery(":hidden")

jquery(":visible")

jquery("div.entrada h2")

jquery("div.entrada > h2")

jquery("tr:nth-child(1)")

jquery("tr:first-child")

jquery("tr:last-child")

jquery("div:only-child")

jquery("td:eq(0)")

jquery("td:first)")

jquery("td:last)")

jquery("td:gt(0)")

jquery("td:lt(3)")

jquery("td:even")

jquery("td:odd")

jquery("div.entrada ~ p")

jquery("div.entrada + p")

jquery("h2:parent")

jquery(":empty")

$('#myDomElement').click( function(){
   alert( 'Click!' );
});

$(document).ready( function(){
   $('.myListElement').click( function(){
     alert(' Click! ');
   });
   
   $('.addNewListElement').click( function(){
     $('<li class="myListElement" />').appendTo('#myList');
   });
} );

$(document).ready( function(){
   $('.myListElement').live( 'click', function(){
     alert(' Click! ');
   });
   
   $('.addNewListElement').click( function(){
     $('<li class="myListElement" />').appendTo('#myList');
   });
} );

$(document).ready( function(){
   $('#myList').delegate( '.myListElement', 'click', function(){
     alert(' Click! ');
   });
   
   $('.addNewListElement').click( function(){
     $('<li class="myListElement" />').appendTo('#myList');
   });
} );

<div class="tab1 tabwidget">
     <div class="tab"> ... </tab>
     <div class="tab> ... </tab>
   </div>
   <div class="tab2 tabwidget">
     <div class="tab"> ... </tab>
     <div class="tab> ... </tab>
   </div>

$('.myElement').click( function(){
   $this = $(this);
   $this.width('300');
   $this.height('300');
   $this.addClass('selected');
})

$('.myElement').click( function(){
   $(this)
     .width('300');
     .height('300');
     .addClass('selected');
})

<script src='http://ajax.googleapis.com/ajax/libs/jquery/1/jquery.min.js"></script>

<link rel='stylesheet' href='URL_craftyslide.css' />

<script src='URL_craftyslide.min'></script>

#pagination li a {
   .......
   background: transparent url(URL_pagination.png) repeat 0 0;
}

#slideshow { /* es el DIV que contiene la galería */
   border: 15px solid #FFF;
   box-shadow: 0 3px 5px #999;
   margin: 0;
   padding: 0;
   position: relative;
}
#slideshow ul { /* la lista que contendrá las imágenes */
   margin: 0;
   overflow: hidden;
   padding: 0;
   position: relative;
}
#slideshow ul li { /* cada item de la lista */
   left:0;
   list-style-type:none;
   margin: 0;
   padding: 0;
   position: absolute;
   top: 0;
}
#pagination { /* la paginación inferior optativa */
   clear: both;
   margin: 25px auto 0;
   padding: 0;
   text-align: center;
}
#pagination li { /* cada item de la paginación */
   display: inline;
   list-style-type: none;
   margin: 0 2px;
}
#pagination li a { /* cada imagen de la paginación es un enlace */
   background: transparent url(URL_pagination.png) repeat 0 0;
   display: inline-block;
   height: 10px;
   text-indent: -10000px;
   width: 10px;
}
#pagination li a.active { /* la imagen cambia cuando se activa */
   background-position:0 10px;
}
.caption { /* el texto optativo que se coloca en el atributo title */
   background: rgba(0,0,0,0.6);
   border-top: 1px solid #000;
   color: #FFF;
   font-family: Helvetica, Arial, sans-serif;
   font-size: 14px;
   font-weight: lighter;
   left: 0;
   margin: 0;
   padding: 10px;
   position: absolute;
   width: 100%;
   z-index: 1;
}

<div id="slideshow">
   <ul>
     <li><img src="URL_IMAGEN_1" title="text imagen 1" /></li>
     <li><img src="URL_IMAGEN_1" title="text imagen 1" /></li>
     <!-- y seguimos agregando tantas etiquetas LI como querra,os -->
   </ul>
</div>

<script> $("#slideshow").craftyslide(); </script>

<script>
  $("#slideshow").craftyslide({
     'width': 550,
     'height': 350,
     'pagination': true,
     'fadetime': 500,
     'delay': 2500
   });
</script>

/**
  * @function
  * @name swap
  * @description Swap two elements in an array
  * @param {array} myArr The target array.
  * @param {int} indexOne The index of the first element to swap.
  * @param {int} indexTwo The index of the second element to swap.
  * @returns {array} The array with the two elements swapped.
  */
function swap(myArr, indexOne, indexTwo){
   var tmpVal = myArr[indexOne];
   myArr[indexOne] = myArr[indexTwo];
   myArr[indexTwo] = tmpVal;
   return myArr;
}

var myArr = ['a', 'b', 'c', 'd'];
console.log( swap( myArr, 0, 1) ); // ["b", "a", "c", "d"]

function bubbleSort(myArr){
   var size = myArr.length;
   
   for( var pass = 1; pass < size; pass++ ){ // outer loop
     for( var left = 0; left < (size - pass); left++){ // inner loop
       var right = left + 1;
       if( myArr[left] > myArr[right] ){
         swap(myArr, left, right);
       }
     }
   }
   
   return myArr;
}

var myArr = ['d', 'f', 'd', 'c', 'a', 'e', 'b'];
console.log( bubbleSort( myArr ) ); // ["a", "b", "c", "d", "d", "e", "f"]

function swap(myArr, indexOne, indexTwo){
   if( indexOne == indexTwo ){
     return myArr;
   }
   var tmpVal = myArr[indexOne];
   myArr[indexOne] = myArr[indexTwo];
   myArr[indexTwo] = tmpVal;
   return myArr;
}

function selectionSort( myArr ){
   var size = myArr.length;
   for( var slot = 0; slot < size -1; slot ++ ){ // outer loop
     var smallest = slot;
     for( var check = slot + 1; check < size; check++ ){ // inner loop
       if( myArr[check] < myArr[smallest] ){
         smallest = check;
       }
     }
     swap( myArr, smallest, slot );
   }
   return myArr;
}

var myArr = ['d', 'f', 'd', 'c', 'a', 'e', 'b'];
console.log( selectionSort( myArr ) ); // ["a", "b", "c", "d", "d", "e", "f"]

$.trim('   Hola Mundo '); // Hola Mundo

$('  Hola Mundo   ').trim();

(function (undefined) {
   
   var utils = (function () {
   
   })();
   
   window.utils = window.$$ = utils;
   
})();

$$('Hola Mundo');

(function (undefined) {
   
   var utils = (function () {
   
     var core = function ( args ) {
       /* ... */
     };
   
     // Methods goes here
   
     // Return
     return core;
   
   })();
   
   window.utils = window.$$ = utils;
   
})();

$$('Hola Mundo');

(function (undefined) {
   
   var utils = (function () {
   
     var core = function ( args ) {
       return new core.fn.init( args );
     };
   
     core.fn = core.prototype = {
       init: function ( args ) {
         core._args = args;
         return core;
       }
     };
   
     // Methods goes here
   
     // Return
     return core;
   
   })();
   
   window.utils = window.$$ = utils;
   
})();

(function (undefined) {
   
   var utils = (function () {
   
      var core = function ( args ) {
       return new core.fn.init( args );
     };
   
     core.fn = core.prototype = {
       init: function ( args ) {
         core._args = args;
         return utils;
       }
     };
   
     // Methods goes here
     core.trim = function (str) {
       core._args && (str = core._args);
       return str.replace(/^\s+|\s+$/g, '');
     };
   
     // Return
     return core;
   
   })();
   
   window.utils = window.$$ = utils;
   
})();

console.log( $$.trim( '  Hola Mundo  ') ) ;  // Retrocompatibilidad con la forma anterior.
console.log( $$('  Hola Mundo  ').trim() ) ; // Nueva invocación por declaración.

core._args && (str = core._args);

if( core._args ){
   str = core._args
}

core._args && (str = core._args);
str || (str = '');
core._args = '';

str = core._args || str || '';
core._args = '';

(function (undefined) {
   
   var utils = (function () {
      var core = function ( args ) {
       return new core.fn.init( args );
     };
   
     core.fn = core.prototype = {
       init: function ( args ) {
         core._args = args;
         return utils;
       }
     };
   
     // Methods goes here
     core.trim = function (str) {
       core._args && (str = core._args);
       str || (str = '');
       core._args = '';
       return str.replace(/^\s+|\s+$/g, '');
     };
   
     // Return
     return core;
   
   })();
   
   window.utils = window.$$ = utils;
   
})();

var sample1 = '  Hello World  ';
var sample2 = '   Good bye Lenin    ';
   
console.log( '1', $$.trim( sample1 ) ); // 'Hello World'
console.log( '2', $$.trim( sample2 ) ); // 'Good bye Lenin'
console.log( '3', $$( sample1 ).trim() ); // 'Hello World'
console.log( '4', $$( sample2 ).trim() ); // 'Good bye Lenin'
console.log( '5', $$.trim( sample2 ) ); // 'Good bye Lenin'
console.log( '6', $$.trim() ); // ''
console.log( '7', $$().trim() ); // ''
console.log( '8', $$.trim() ); // ''
console.log( '9', $$( sample1).trim( sample2 ) ); // 'Hello World'
console.log( '10', $$().trim() ); // ''
console.log( '11', $$( sample1 ).trim( sample2 ) ); // 'Hello World'
console.log( '12', $$.trim() ); // ''
console.log( '13', $$( sample1 ).trim( sample2 ) ); // 'Hello World'
console.log( '14', $$().trim() ); // ''
console.log( '15', $$( sample1 ).trim( sample2 ) ); //'Hello World'

$$('  Hello World  ').trim().method2().method3(); // And so on...