jQuery .show()

With no parameters, the .show() method is the simplest way to display an element:

$( ".target" ).show();

The matched elements will be revealed immediately, with no animation. This is roughly equivalent to calling .css( "display", "block"), except that the display property is restored to whatever it was initially. If an element has a display value of inline, then is hidden and shown, it will once again be displayed inline.

Note: If using !important in your styles, such as display: none !important, it is necessary to override the style using .css( "display", "block !important") should you wish for .show() to function correctly.

When a duration, a plain object, or a "complete" function is provided, .show() becomes an animation method. The .show() method animates the width, height, and opacity of the matched elements simultaneously.

Durations are given in milliseconds; higher values indicate slower animations, not faster ones. The strings 'fast' and 'slow' can be supplied to indicate durations of 200 and 600 milliseconds, respectively.

As of jQuery 1.4.3, an optional string naming an easing function may be used. Easing functions specify the speed at which the animation progresses at different points within the animation. The only easing implementations in the jQuery library are the default, called swing, and one that progresses at a constant pace, called linear. More easing functions are available with the use of plug-ins, most notably the jQuery UI suite.

If supplied, the callback is fired once the animation is complete. This can be useful for stringing different animations together in sequence. The callback is not sent any arguments, but this is set to the DOM element being animated. If multiple elements are animated, it is important to note that the callback is executed once per matched element, not once for the animation as a whole.

We can animate any element, such as a simple image:

<div id="clickme">
 Click here
</div>
<img id="book" src="book.png" alt="" width="100" height="123">
With the element initially hidden, we can show it slowly:
$( "#clickme" ).click(function() {
 $( "#book" ).show( "slow", function() {
 // Animation complete.
 });
});